diff --git a/configure.py b/configure.py
index 631d5fa6f..8c0b18f6d 100644
--- a/configure.py
+++ b/configure.py
@@ -779,7 +779,7 @@ config.libs = [
             Object(NonMatching, "JSystem/JKernel/JKRDvdFile.cpp"),
             Object(Matching,    "JSystem/JKernel/JKRDvdRipper.cpp"),
             Object(NonMatching, "JSystem/JKernel/JKRDvdAramRipper.cpp"),
-            Object(NonMatching, "JSystem/JKernel/JKRDecomp.cpp"),
+            Object(Matching,    "JSystem/JKernel/JKRDecomp.cpp"),
         ],
     ),
     JSystemLib(
diff --git a/include/JSystem/JKernel/JKRAram.h b/include/JSystem/JKernel/JKRAram.h
index e66c696a6..a9f2564e4 100644
--- a/include/JSystem/JKernel/JKRAram.h
+++ b/include/JSystem/JKernel/JKRAram.h
@@ -33,7 +33,7 @@ public:
     /* 0x84 */ u32 mStackArray[3];
 
 public:
-    static JKRAram* create(u32, u32, long, long, long);
+    static JKRAram* create(u32, u32, s32, s32, s32);
     static bool checkOkAddress(u8*, u32, JKRAramBlock*, u32);
     static void changeGroupIdIfNeed(u8*, int);
     static JKRAramBlock* mainRamToAram(u8*, u32, u32, JKRExpandSwitch, u32, JKRHeap*, int);
diff --git a/include/JSystem/JKernel/JKRAramArchive.h b/include/JSystem/JKernel/JKRAramArchive.h
index 5f8d28413..392be1be5 100644
--- a/include/JSystem/JKernel/JKRAramArchive.h
+++ b/include/JSystem/JKernel/JKRAramArchive.h
@@ -9,10 +9,10 @@ class JKRDvdFile;
 
 class JKRAramArchive : public JKRArchive {
 public:
-    JKRAramArchive(long, JKRArchive::EMountDirection);
+    JKRAramArchive(s32, JKRArchive::EMountDirection);
     virtual ~JKRAramArchive();
 
-    bool open(long);
+    bool open(s32);
     u32 getAramAddress_Entry(SDIFileEntry*);
     u32 getAramAddress(char const*);
 
diff --git a/include/JSystem/JKernel/JKRAramStream.h b/include/JSystem/JKernel/JKRAramStream.h
index cdbfbd5ca..ee36d5fcf 100644
--- a/include/JSystem/JKernel/JKRAramStream.h
+++ b/include/JSystem/JKernel/JKRAramStream.h
@@ -42,7 +42,7 @@ private:
     /* vt[03] */ void* run(void); /* override */
 
 public:
-    static JKRAramStream* create(long);
+    static JKRAramStream* create(s32);
 
     static s32 readFromAram(void);
     static s32 writeToAram(JKRAramStreamCommand*);
@@ -60,7 +60,7 @@ private:
     static JKRHeap* transHeap;
 };
 
-inline JKRAramStream* JKRCreateAramStreamManager(long priority) {
+inline JKRAramStream* JKRCreateAramStreamManager(s32 priority) {
     return JKRAramStream::create(priority);
 }
 
diff --git a/include/JSystem/JKernel/JKRArchive.h b/include/JSystem/JKernel/JKRArchive.h
index f3bb0f5bd..46ebcd0c4 100644
--- a/include/JSystem/JKernel/JKRArchive.h
+++ b/include/JSystem/JKernel/JKRArchive.h
@@ -115,7 +115,7 @@ public:
 
 protected:
     JKRArchive();
-    JKRArchive(long, EMountMode);
+    JKRArchive(s32, EMountMode);
 
 public:
     bool getDirEntry(SDirEntry*, u32) const;
diff --git a/include/JSystem/JKernel/JKRAssertHeap.h b/include/JSystem/JKernel/JKRAssertHeap.h
index 48a79d95e..d0e8d876c 100644
--- a/include/JSystem/JKernel/JKRAssertHeap.h
+++ b/include/JSystem/JKernel/JKRAssertHeap.h
@@ -5,7 +5,7 @@
 
 class JKRAssertHeap : public JKRHeap {
 protected:
-    JKRAssertHeap(void*, unsigned long, JKRHeap*, bool);
+    JKRAssertHeap(void*, u32, JKRHeap*, bool);
     virtual ~JKRAssertHeap();
 
 public:
diff --git a/include/JSystem/JKernel/JKRCompArchive.h b/include/JSystem/JKernel/JKRCompArchive.h
index 4fb13152a..14d24b7eb 100644
--- a/include/JSystem/JKernel/JKRCompArchive.h
+++ b/include/JSystem/JKernel/JKRCompArchive.h
@@ -8,10 +8,10 @@ class JKRDvdFile;
 
 class JKRCompArchive : public JKRArchive {
 public:
-    JKRCompArchive(long, JKRArchive::EMountDirection);
+    JKRCompArchive(s32, JKRArchive::EMountDirection);
     virtual ~JKRCompArchive();
 
-    bool open(long);
+    bool open(s32);
 
     /* vt[09] */ void removeResourceAll(void); /* override */
     /* vt[10] */ bool removeResource(void*);   /* override */
diff --git a/include/JSystem/JKernel/JKRDecomp.h b/include/JSystem/JKernel/JKRDecomp.h
index e7ef48c68..c4b9c949a 100644
--- a/include/JSystem/JKernel/JKRDecomp.h
+++ b/include/JSystem/JKernel/JKRDecomp.h
@@ -32,13 +32,13 @@ public:
 
 class JKRDecomp : public JKRThread {
 private:
-    JKRDecomp(long);
+    JKRDecomp(s32);
     virtual ~JKRDecomp();
 
     /* vt[03] */ virtual void* run(); /* override */
 
 public:
-    static JKRDecomp* create(long);
+    static JKRDecomp* create(s32);
     static JKRDecompCommand* prepareCommand(u8*, u8*, u32, u32, JKRDecompCommand::AsyncCallback);
     static void sendCommand(JKRDecompCommand*);
     static bool sync(JKRDecompCommand*, int);
@@ -50,7 +50,7 @@ public:
     static JKRCompression checkCompressed(u8*);
 
     static JKRDecomp* sDecompObject;
-    static OSMessage sMessageBuffer[8];
+    static OSMessage sMessageBuffer[4];
     static OSMessageQueue sMessageQueue;
 };
 
@@ -58,7 +58,7 @@ inline void JKRDecompress(u8* srcBuffer, u8* dstBuffer, u32 srcLength, u32 dstLe
     JKRDecomp::orderSync(srcBuffer, dstBuffer, srcLength, dstLength);
 }
 
-inline JKRDecomp* JKRCreateDecompManager(long priority) {
+inline JKRDecomp* JKRCreateDecompManager(s32 priority) {
     return JKRDecomp::create(priority);
 }
 
diff --git a/include/JSystem/JKernel/JKRDvdAramRipper.h b/include/JSystem/JKernel/JKRDvdAramRipper.h
index 6c3ba1de7..50957d4e0 100644
--- a/include/JSystem/JKernel/JKRDvdAramRipper.h
+++ b/include/JSystem/JKernel/JKRDvdAramRipper.h
@@ -34,7 +34,7 @@ public:
 class JKRDvdFile;
 class JKRDvdAramRipper {
 public:
-    static JKRAramBlock* loadToAram(long, u32, JKRExpandSwitch, u32, u32);
+    static JKRAramBlock* loadToAram(s32, u32, JKRExpandSwitch, u32, u32);
     static JKRAramBlock* loadToAram(JKRDvdFile*, u32, JKRExpandSwitch, u32, u32);
     static JKRADCommand* loadToAram_Async(JKRDvdFile*, u32, JKRExpandSwitch, void (*)(u32), u32,
                                           u32);
diff --git a/include/JSystem/JKernel/JKRDvdFile.h b/include/JSystem/JKernel/JKRDvdFile.h
index 1ea018241..c0c1ea3e2 100644
--- a/include/JSystem/JKernel/JKRDvdFile.h
+++ b/include/JSystem/JKernel/JKRDvdFile.h
@@ -52,7 +52,7 @@ public:
     /* 0xF4 */ OSThread* mOSThread;
 
 public:
-    static void doneProcess(long, DVDFileInfo*);
+    static void doneProcess(s32, DVDFileInfo*);
 
     static JSUList<JKRDvdFile>& getDvdList() { return sDvdList; }
 
diff --git a/include/JSystem/JKernel/JKRDvdRipper.h b/include/JSystem/JKernel/JKRDvdRipper.h
index 7534f9ee9..83fabe2a4 100644
--- a/include/JSystem/JKernel/JKRDvdRipper.h
+++ b/include/JSystem/JKernel/JKRDvdRipper.h
@@ -38,7 +38,7 @@ public:
 
     static void* loadToMainRAM(char const*, u8*, JKRExpandSwitch, u32, JKRHeap*, EAllocDirection,
                                u32, int*);
-    static void* loadToMainRAM(long, u8*, JKRExpandSwitch, u32, JKRHeap*, EAllocDirection, u32,
+    static void* loadToMainRAM(s32, u8*, JKRExpandSwitch, u32, JKRHeap*, EAllocDirection, u32,
                                int*);
     static void* loadToMainRAM(JKRDvdFile*, u8*, JKRExpandSwitch, u32, JKRHeap*, EAllocDirection,
                                u32, int*);
diff --git a/include/JSystem/JKernel/JKRFile.h b/include/JSystem/JKernel/JKRFile.h
index 4e1be4db8..ed9d35a2c 100644
--- a/include/JSystem/JKernel/JKRFile.h
+++ b/include/JSystem/JKernel/JKRFile.h
@@ -8,7 +8,7 @@ public:
     JKRFile() : mIsAvailable(false) {}
     virtual ~JKRFile() {}
 
-    s32 read(void*, long, long);
+    s32 read(void*, s32, s32);
 
     bool isAvailable() const { return mIsAvailable; }
 
diff --git a/include/JSystem/JKernel/JKRFileLoader.h b/include/JSystem/JKernel/JKRFileLoader.h
index c02dedc10..9e05be16a 100644
--- a/include/JSystem/JKernel/JKRFileLoader.h
+++ b/include/JSystem/JKernel/JKRFileLoader.h
@@ -43,7 +43,7 @@ public:
     static bool removeResource(void*, JKRFileLoader*);
     static bool detachResource(void*, JKRFileLoader*);
     static JKRFileLoader* findVolume(const char**);
-    static const char* fetchVolumeName(char*, long, const char*);
+    static const char* fetchVolumeName(char*, s32, const char*);
 
     static JKRFileLoader* getCurrentVolume() { return sCurrentVolume; }
     static void setCurrentVolume(JKRFileLoader* fileLoader) { sCurrentVolume = fileLoader; }
diff --git a/include/JSystem/JKernel/JKRMemArchive.h b/include/JSystem/JKernel/JKRMemArchive.h
index 54fc72459..93c051920 100644
--- a/include/JSystem/JKernel/JKRMemArchive.h
+++ b/include/JSystem/JKernel/JKRMemArchive.h
@@ -11,13 +11,13 @@ enum JKRMemBreakFlag {
 class JKRMemArchive : public JKRArchive {
 public:
     JKRMemArchive();
-    JKRMemArchive(long, JKRArchive::EMountDirection);
+    JKRMemArchive(s32, JKRArchive::EMountDirection);
     virtual ~JKRMemArchive();
 
     void fixedInit(s32);
     bool mountFixed(void*, JKRMemBreakFlag);
     void unmountFixed();
-    bool open(long, JKRArchive::EMountDirection);
+    bool open(s32, JKRArchive::EMountDirection);
     bool open(void*, u32, JKRMemBreakFlag);
 
     /* vt[09] */ void removeResourceAll(void); /* override */
diff --git a/src/JSystem/JKernel/JKRAram.cpp b/src/JSystem/JKernel/JKRAram.cpp
index e20e34068..1aad48247 100644
--- a/src/JSystem/JKernel/JKRAram.cpp
+++ b/src/JSystem/JKernel/JKRAram.cpp
@@ -24,7 +24,7 @@ static u8* nextSrcData(u8*);
 JKRAram* JKRAram::sAramObject;
 
 /* 802B42C4-802B4360       .text create__7JKRAramFUlUllll */
-JKRAram* JKRAram::create(u32 aram_audio_buffer_size, u32 aram_audio_graph_size, long stream_priority, long decomp_priority, long piece_priority) {
+JKRAram* JKRAram::create(u32 aram_audio_buffer_size, u32 aram_audio_graph_size, s32 stream_priority, s32 decomp_priority, s32 piece_priority) {
     if (!sAramObject) {
         sAramObject = new (JKRHeap::getSystemHeap(), 0)
             JKRAram(aram_audio_buffer_size, aram_audio_graph_size, piece_priority);
@@ -40,7 +40,7 @@ OSMessage JKRAram::sMessageBuffer[4] = { NULL, NULL, NULL, NULL };
 OSMessageQueue JKRAram::sMessageQueue = {0};
 
 /* 802B4360-802B44D8       .text __ct__7JKRAramFUlUll */
-JKRAram::JKRAram(u32 audio_buffer_size, u32 audio_graph_size, long priority) : JKRThread(0x4000, 0x10, priority) {
+JKRAram::JKRAram(u32 audio_buffer_size, u32 audio_graph_size, s32 priority) : JKRThread(0x4000, 0x10, priority) {
     u32 aramBase = ARInit(mStackArray, ARRAY_SIZE(mStackArray));
     ARQInit();
 
@@ -323,14 +323,14 @@ static u32 srcAddress;
 static u32 fileOffset;
 static u32 readCount;
 static u32 maxDest;
-static bool sIsInitMutex;
+static bool isInitMutex;
 
 /* 802B4D4C-802B4F20       .text JKRDecompressFromAramToMainRam__FUlPvUlUlUl */
 static int JKRDecompressFromAramToMainRam(u32 src, void* dst, u32 srcLength, u32 dstLength, u32 offset) {
     BOOL interrupts = OSDisableInterrupts();
-    if (sIsInitMutex == false) {
+    if (isInitMutex == false) {
         OSInitMutex(&decompMutex);
-        sIsInitMutex = true;
+        isInitMutex = true;
     }
     OSRestoreInterrupts(interrupts);
     OSLockMutex(&decompMutex);
diff --git a/src/JSystem/JKernel/JKRDecomp.cpp b/src/JSystem/JKernel/JKRDecomp.cpp
index 2b3c514b2..e07fdda8c 100644
--- a/src/JSystem/JKernel/JKRDecomp.cpp
+++ b/src/JSystem/JKernel/JKRDecomp.cpp
@@ -4,79 +4,291 @@
 //
 
 #include "JSystem/JKernel/JKRDecomp.h"
+#include "JSystem/JKernel/JKRAramPiece.h"
 #include "dolphin/types.h"
 
+JKRDecomp* JKRDecomp::sDecompObject;
+
 /* 802BE890-802BE8F0       .text create__9JKRDecompFl */
-void JKRDecomp::create(long) {
-    /* Nonmatching */
+JKRDecomp* JKRDecomp::create(s32 priority) {
+    if (!sDecompObject) {
+        sDecompObject = new (JKRHeap::getSystemHeap(), 0) JKRDecomp(priority);
+    }
+
+    return sDecompObject;
 }
 
+OSMessage JKRDecomp::sMessageBuffer[4] = {NULL};
+OSMessageQueue JKRDecomp::sMessageQueue = {0};
+
 /* 802BE8F0-802BE940       .text __ct__9JKRDecompFl */
-JKRDecomp::JKRDecomp(long) {
-    /* Nonmatching */
+JKRDecomp::JKRDecomp(s32 priority) : JKRThread(0x4000, 0x10, priority) {
+    resume();
 }
 
 /* 802BE940-802BE9A0       .text __dt__9JKRDecompFv */
-JKRDecomp::~JKRDecomp() {
-    /* Nonmatching */
-}
+JKRDecomp::~JKRDecomp() {}
 
 /* 802BE9A0-802BEA68       .text run__9JKRDecompFv */
-void JKRDecomp::run() {
-    /* Nonmatching */
+void* JKRDecomp::run() {
+    OSInitMessageQueue(&sMessageQueue, sMessageBuffer, 4);
+    while (true) {
+        OSMessage message;
+        OSReceiveMessage(&sMessageQueue, &message, OS_MESSAGE_BLOCK);
+
+        JKRDecompCommand* command = (JKRDecompCommand*)message;
+        decode(command->mSrcBuffer, command->mDstBuffer, command->mSrcLength, command->mDstLength);
+
+        if (command->field_0x20 != 0) {
+            if (command->field_0x20 == 1) {
+                JKRAramPiece::sendCommand(command->mAMCommand);
+            }
+            continue;
+        }
+
+        if (command->mCallback) {
+            (*command->mCallback)((u32)command);
+            continue;
+        }
+
+        if (command->field_0x1c) {
+            OSSendMessage(command->field_0x1c, (OSMessage)1, OS_MESSAGE_NOBLOCK);
+        } else {
+            OSSendMessage(&command->mMessageQueue, (OSMessage)1, OS_MESSAGE_NOBLOCK);
+        }
+    }
 }
 
 /* 802BEA68-802BEAE0       .text prepareCommand__9JKRDecompFPUcPUcUlUlPFUl_v */
-void JKRDecomp::prepareCommand(unsigned char*, unsigned char*, unsigned long, unsigned long, void (*)(unsigned long)) {
-    /* Nonmatching */
+JKRDecompCommand* JKRDecomp::prepareCommand(u8* srcBuffer, u8* dstBuffer, u32 srcLength, u32 dstLength, JKRDecompCommand::AsyncCallback callback) {
+    JKRDecompCommand* command = new (JKRHeap::getSystemHeap(), -4) JKRDecompCommand();
+    command->mSrcBuffer = srcBuffer;
+    command->mDstBuffer = dstBuffer;
+    command->mSrcLength = srcLength;
+    command->mDstLength = dstLength;
+    command->mCallback = callback;
+    return command;
 }
 
 /* 802BEAE0-802BEB10       .text sendCommand__9JKRDecompFP16JKRDecompCommand */
-void JKRDecomp::sendCommand(JKRDecompCommand*) {
-    /* Nonmatching */
+void JKRDecomp::sendCommand(JKRDecompCommand* command) {
+    OSSendMessage(&sMessageQueue, command, OS_MESSAGE_BLOCK);
 }
 
 /* 802BEB10-802BEB44       .text orderAsync__9JKRDecompFPUcPUcUlUlPFUl_v */
-void JKRDecomp::orderAsync(unsigned char*, unsigned char*, unsigned long, unsigned long, void (*)(unsigned long)) {
-    /* Nonmatching */
+JKRDecompCommand* JKRDecomp::orderAsync(u8* srcBuffer, u8* dstBuffer, u32 srcLength, u32 dstLength, JKRDecompCommand::AsyncCallback callback) {
+    JKRDecompCommand* command =
+        prepareCommand(srcBuffer, dstBuffer, srcLength, dstLength, callback);
+    sendCommand(command);
+    return command;
 }
 
 /* 802BEB44-802BEB98       .text sync__9JKRDecompFP16JKRDecompCommandi */
-void JKRDecomp::sync(JKRDecompCommand*, int) {
-    /* Nonmatching */
+bool JKRDecomp::sync(JKRDecompCommand* command, int isNonBlocking) {
+    OSMessage message;
+    bool result;
+    if (isNonBlocking == JKRDECOMP_SYNC_BLOCKING) {
+        OSReceiveMessage(&command->mMessageQueue, &message, OS_MESSAGE_BLOCK);
+        result = true;
+    } else {
+        result =
+            OSReceiveMessage(&command->mMessageQueue, &message, OS_MESSAGE_NOBLOCK) != FALSE;
+    }
+
+    return result;
 }
 
 /* 802BEB98-802BEBEC       .text orderSync__9JKRDecompFPUcPUcUlUl */
-void JKRDecomp::orderSync(unsigned char*, unsigned char*, unsigned long, unsigned long) {
-    /* Nonmatching */
+bool JKRDecomp::orderSync(u8* srcBuffer, u8* dstBuffer, u32 srcLength, u32 dstLength) {
+    JKRDecompCommand* command = orderAsync(srcBuffer, dstBuffer, srcLength, dstLength, NULL);
+    bool result = sync(command, JKRDECOMP_SYNC_BLOCKING);
+    delete command;
+    return result;
 }
 
 /* 802BEBEC-802BEC68       .text decode__9JKRDecompFPUcPUcUlUl */
-void JKRDecomp::decode(unsigned char*, unsigned char*, unsigned long, unsigned long) {
-    /* Nonmatching */
+void JKRDecomp::decode(u8* srcBuffer, u8* dstBuffer, u32 srcLength, u32 dstLength) {
+    JKRCompression compression = checkCompressed(srcBuffer);
+    if (compression == COMPRESSION_YAY0) {
+        decodeSZP(srcBuffer, dstBuffer, srcLength, dstLength);
+    } else if (compression == COMPRESSION_YAZ0) {
+        decodeSZS(srcBuffer, dstBuffer, srcLength, dstLength);
+    }
 }
 
 /* 802BEC68-802BEE24       .text decodeSZP__9JKRDecompFPUcPUcUlUl */
-void JKRDecomp::decodeSZP(unsigned char*, unsigned char*, unsigned long, unsigned long) {
-    /* Nonmatching */
+void JKRDecomp::decodeSZP(u8* src, u8* dst, u32 srcLength, u32 dstLength) {
+    int srcChunkOffset;
+    int count;
+    int dstOffset;
+    u32 length = srcLength;
+    int linkInfo;
+    int offset;
+    int i;
+
+    int decodedSize = READU32_BE(src, 4);
+    int linkTableOffset = READU32_BE(src, 8);
+    int srcDataOffset = READU32_BE(src, 12);
+
+    dstOffset = 0;
+    u32 counter = 0;
+    srcChunkOffset = 16;
+
+    u32 chunkBits;
+    if (srcLength == 0)
+        return;
+    if (dstLength > decodedSize)
+        return;
+
+    do
+    {
+        if (counter == 0)
+        {
+            chunkBits = READU32_BE(src, srcChunkOffset);
+            srcChunkOffset += sizeof(u32);
+            counter = sizeof(u32) * 8;
+        }
+
+        if (chunkBits & 0x80000000)
+        {
+            if (dstLength == 0)
+            {
+                dst[dstOffset] = src[srcDataOffset];
+                length--;
+                if (length == 0)
+                    return;
+            }
+            else
+            {
+                dstLength--;
+            }
+            dstOffset++;
+            srcDataOffset++;
+        }
+        else
+        {
+            linkInfo = src[linkTableOffset] << 8 | src[linkTableOffset + 1];
+            linkTableOffset += sizeof(u16);
+
+            offset = dstOffset - (linkInfo & 0xFFF);
+            count = (linkInfo >> 12);
+            if (count == 0)
+            {
+                count = (u32)src[srcDataOffset++] + 0x12;
+            }
+            else
+                count += 2;
+
+            if (count > decodedSize - dstOffset)
+                count = decodedSize - dstOffset;
+
+            for (i = 0; i < count; i++, dstOffset++, offset++)
+            {
+                if (dstLength == 0)
+                {
+                    dst[dstOffset] = dst[offset - 1];
+                    length--;
+                    if (length == 0)
+                        return;
+                }
+                else
+                    dstLength--;
+            }
+        }
+
+        chunkBits <<= 1;
+        counter--;
+    } while (dstOffset < decodedSize);
 }
 
 /* 802BEE24-802BEF08       .text decodeSZS__9JKRDecompFPUcPUcUlUl */
-void JKRDecomp::decodeSZS(unsigned char*, unsigned char*, unsigned long, unsigned long) {
-    /* Nonmatching */
+void JKRDecomp::decodeSZS(u8* src_buffer, u8* dst_buffer, u32 srcSize, u32 dstSize) {
+    u8* decompEnd;
+    u8* copyStart;
+    s32 copyByteCount;
+    s32 chunkBitsLeft = 0;
+    s32 chunkBits;
+
+    decompEnd = dst_buffer + *(int*)(src_buffer + 4) - dstSize;
+
+    if (srcSize == 0) {
+        return;
+    }
+    if (dstSize > *(u32*)src_buffer) {
+        return;
+    }
+
+    u8* curSrcPos = src_buffer + 0x10;
+    do {
+        if (chunkBitsLeft == 0) {
+            chunkBits = curSrcPos[0];
+            chunkBitsLeft = 8;
+            curSrcPos++;
+        }
+        if ((chunkBits & 0x80) != 0) {
+            if (dstSize == 0) {
+                dst_buffer[0] = curSrcPos[0];
+                srcSize--;
+                dst_buffer++;
+                if (srcSize == 0)
+                    return;
+            } else {
+                dstSize--;
+            }
+            curSrcPos++;
+        } else {
+            u32 local_28 = curSrcPos[1] | (curSrcPos[0] & 0xF) << 8;
+            u32 r31 = curSrcPos[0] >> 4;
+            curSrcPos += 2;
+            copyStart = dst_buffer - local_28;
+            if (r31 == 0) {
+                copyByteCount = curSrcPos[0] + 0x12;
+                curSrcPos++;
+            } else {
+                copyByteCount = r31 + 2;
+            }
+            do {
+                if (dstSize == 0) {
+                    dst_buffer[0] = copyStart[-1];
+                    srcSize--;
+                    dst_buffer++;
+                    if (srcSize == 0)
+                        return;
+                } else {
+                    dstSize--;
+                }
+                copyByteCount--;
+                copyStart++;
+            } while (copyByteCount != 0);
+        }
+        chunkBits <<= 1;
+        chunkBitsLeft--;
+    } while (dst_buffer != decompEnd);
 }
 
 /* 802BEF08-802BEF58       .text checkCompressed__9JKRDecompFPUc */
-void JKRDecomp::checkCompressed(unsigned char*) {
-    /* Nonmatching */
+JKRCompression JKRDecomp::checkCompressed(u8* src) {
+    if ((src[0] == 'Y') && (src[1] == 'a') && (src[3] == '0')) {
+        if (src[2] == 'y') {
+            return COMPRESSION_YAY0;
+        }
+
+        if (src[2] == 'z') {
+            return COMPRESSION_YAZ0;
+        }
+    }
+
+    return COMPRESSION_NONE;
 }
 
 /* 802BEF58-802BEFA8       .text __ct__16JKRDecompCommandFv */
 JKRDecompCommand::JKRDecompCommand() {
-    /* Nonmatching */
+    OSInitMessageQueue(&mMessageQueue, &mMessage, 1);
+    mCallback = NULL;
+    field_0x1c = NULL;
+    mThis = this;
+    field_0x20 = 0;
 }
 
 /* 802BEFA8-802BEFE4       .text __dt__16JKRDecompCommandFv */
-JKRDecompCommand::~JKRDecompCommand() {
-    /* Nonmatching */
-}
+JKRDecompCommand::~JKRDecompCommand() {}
diff --git a/src/JSystem/JKernel/JKRFile.cpp b/src/JSystem/JKernel/JKRFile.cpp
index 04cb11a6c..8d6654b1f 100644
--- a/src/JSystem/JKernel/JKRFile.cpp
+++ b/src/JSystem/JKernel/JKRFile.cpp
@@ -8,7 +8,7 @@
 #include "dolphin/vi/vi.h"
 
 /* 802BC610-802BC6B4       .text read__7JKRFileFPvll */
-s32 JKRFile::read(void* data, s32 length, long offset) {
+s32 JKRFile::read(void* data, s32 length, s32 offset) {
     JUT_ASSERT(34, ( length & 0x1f ) == 0);
     while (true) {
         s32 result = readData(data, length, offset);
diff --git a/src/JSystem/JKernel/JKRFileCache.cpp b/src/JSystem/JKernel/JKRFileCache.cpp
index 89f60a249..7f91ceff4 100644
--- a/src/JSystem/JKernel/JKRFileCache.cpp
+++ b/src/JSystem/JKernel/JKRFileCache.cpp
@@ -149,7 +149,7 @@ void* JKRFileCache::getResource(const char* path) {
 }
 
 /* 802B7564-802B7630       .text getResource__12JKRFileCacheFUlPCc */
-void* JKRFileCache::getResource(unsigned long, const char* path) {
+void* JKRFileCache::getResource(u32, const char* path) {
     JUT_ASSERT(303, isMounted());
 
     char finalPath[256];
diff --git a/src/JSystem/JKernel/JKRFileLoader.cpp b/src/JSystem/JKernel/JKRFileLoader.cpp
index 397d3e3fc..3c28189a3 100644
--- a/src/JSystem/JKernel/JKRFileLoader.cpp
+++ b/src/JSystem/JKernel/JKRFileLoader.cpp
@@ -127,7 +127,7 @@ JKRFileLoader* JKRFileLoader::findVolume(const char** volumeName) {
 static char rootPath[2] = "/";
 
 /* 802B6B44-802B6C20       .text fetchVolumeName__13JKRFileLoaderFPclPCc */
-const char* JKRFileLoader::fetchVolumeName(char* buffer, long bufferSize, const char* path) {
+const char* JKRFileLoader::fetchVolumeName(char* buffer, s32 bufferSize, const char* path) {
     if (strcmp(path, "/") == 0) {
         strcpy(buffer, rootPath);
         return rootPath;
diff --git a/src/JSystem/JKernel/JKRMemArchive.cpp b/src/JSystem/JKernel/JKRMemArchive.cpp
index 3216b6c56..25501e5ba 100644
--- a/src/JSystem/JKernel/JKRMemArchive.cpp
+++ b/src/JSystem/JKernel/JKRMemArchive.cpp
@@ -56,10 +56,10 @@ void JKRMemArchive::fixedInit(s32 param_1) {
 
 /* 802B9740-802B9810       .text mountFixed__13JKRMemArchiveFPv15JKRMemBreakFlag */
 bool JKRMemArchive::mountFixed(void* param_1, JKRMemBreakFlag param_2) {
-    if (check_mount_already((long)param_1)) {
+    if (check_mount_already((s32)param_1)) {
         return false;
     }
-	fixedInit((long)param_1);
+	fixedInit((s32)param_1);
 	if (!open(param_1, 0xffff, param_2)) {
         return false;
     }