Green shells tag, and added comments I neglected to add before.

src/actors/falling_rock/render.inc.c

@@ -59,6 +59,7 @@ void render_actor_falling_rock(Camera* camera, struct FallingRock* rock) {
         return;
     }
     gSPDisplayList(gDisplayListHead++, d_course_choco_mountain_dl_falling_rock);
-    FrameInterpolation_RecordCloseChild();
 
+    // @port Pop the transform id.
+    FrameInterpolation_RecordCloseChild();
 }

src/engine/objects/GrandPrixBalloons.cpp

@@ -106,6 +106,7 @@ void OGrandPrixBalloons::func_80053D74(s32 objectIndex, UNUSED s32 arg1, s32 ver
 
     Vtx* vtx = (Vtx*) LOAD_ASSET_RAW(common_vtx_hedgehog);
 
+    // @port: Tag the transform.
     FrameInterpolation_RecordOpenChild("Balloon", TAG_ITEM_ADDR(object)); //Not working properly just yet
 
     if (gMatrixHudCount <= MTX_HUD_POOL_SIZE_MAX) {
@@ -119,6 +120,7 @@ void OGrandPrixBalloons::func_80053D74(s32 objectIndex, UNUSED s32 arg1, s32 ver
         gSPDisplayList(gDisplayListHead++, (Gfx*)common_rectangle_display);
     }
 
+    // @port Pop the transform id.
     FrameInterpolation_RecordCloseChild();
 }
 

src/racing/actors.c

@@ -34,6 +34,7 @@
 #include <assets/wario_stadium_data.h>
 #include <assets/frappe_snowland_data.h>
 #include "port/Game.h"
+#include "port/interpolation/FrameInterpolation.h"
 
 // Appears to be textures
 // or tluts
@@ -707,6 +708,9 @@ void render_actor_shell(Camera* camera, Mat4 matrix, struct ShellActor* shell) {
     //! @todo Is this making the shell spin?
     // Is it doing this by modifying a an address?
     uintptr_t phi_t3;
+    
+    // @port: Tag the transform.
+    FrameInterpolation_RecordOpenChild("Shell", TAG_ITEM_ADDR(shell));
 
     f32 temp_f0 =
         is_within_render_distance(camera->pos, shell->pos, camera->rot[1], 0, gCameraZoom[camera - camera1], 490000.0f);
@@ -749,6 +753,9 @@ void render_actor_shell(Camera* camera, Mat4 matrix, struct ShellActor* shell) {
     } else {
         gSPDisplayList(gDisplayListHead++, D_0D005368);
     }
+
+    // @port Pop the transform id.
+    FrameInterpolation_RecordCloseChild();
 }
 
 UNUSED s16 D_802B8808[] = { 0x0014, 0x0028, 0x0000, 0x0000 };

src/render_player.c

@@ -1484,6 +1484,7 @@ void render_player_shadow(Player* player, s8 playerId, s8 screenId) {
     UNUSED Vec3f pad2;
     f32 var_f2;
 
+    // @port: Tag the transform.
     FrameInterpolation_RecordOpenChild("Kart Shadow", TAG_ITEM_ADDR(player));
     temp_t9 = (u16) (player->unk_048[screenId] + player->rotation[1] + player->unk_0C0) / 128; // << 7) & 0xFFFF;
     spC0 = -player->rotation[1] - player->unk_0C0;
@@ -1548,6 +1549,8 @@ void render_player_shadow(Player* player, s8 playerId, s8 screenId) {
 
     gSPDisplayList(gDisplayListHead++, common_square_plain_render);
     gSPTexture(gDisplayListHead++, 1, 1, 0, G_TX_RENDERTILE, G_OFF);
+
+    // @port Pop the transform id.
     FrameInterpolation_RecordCloseChild();
 }