diff --git a/LEGO1/mxnextactiondatastart.h b/LEGO1/mxnextactiondatastart.h
index cf38242c..1ef99a70 100644
--- a/LEGO1/mxnextactiondatastart.h
+++ b/LEGO1/mxnextactiondatastart.h
@@ -4,8 +4,17 @@
 #include "mxcore.h"
 
 // VTABLE 0x100dc9a0
+// SIZE 0x14
 class MxNextActionDataStart : public MxCore {
 public:
+	// inlined constructor at 0x100c1847
+	inline MxNextActionDataStart(MxU32 p_objectId, MxS16 p_unk24val, MxU32 p_data)
+	{
+		m_objectId = p_objectId;
+		m_unk24val = p_unk24val;
+		m_data = p_data;
+	}
+
 	// OFFSET: LEGO1 0x100c1900
 	inline virtual const char* ClassName() const override // vtable+0xc
 	{
@@ -18,6 +27,11 @@ class MxNextActionDataStart : public MxCore {
 	{
 		return !strcmp(name, MxNextActionDataStart::ClassName()) || MxCore::IsA(name);
 	}
+
+private:
+	MxU32 m_objectId;
+	MxS16 m_unk24val;
+	MxU32 m_data;
 };
 
 #endif // MXNEXTACTIONDATASTART_H
diff --git a/LEGO1/mxstreamcontroller.cpp b/LEGO1/mxstreamcontroller.cpp
index 72f77b33..1fb3ae03 100644
--- a/LEGO1/mxstreamcontroller.cpp
+++ b/LEGO1/mxstreamcontroller.cpp
@@ -2,6 +2,9 @@
 
 #include "legoomni.h"
 #include "mxautolocker.h"
+#include "mxnextactiondatastart.h"
+
+DECOMP_SIZE_ASSERT(MxNextActionDataStart, 0x14)
 
 // OFFSET: LEGO1 0x100c0b90 STUB
 MxStreamController::MxStreamController()
@@ -74,16 +77,32 @@ MxResult MxStreamController::vtable0x24(undefined4 p_unknown)
 	return FAILURE;
 }
 
+// OFFSET: LEGO1 0x100c1800 STUB
+MxResult MxStreamController::FUN_100c1800(MxDSAction* p_action, MxU32 p_val)
+{
+	MxNextActionDataStart* dataActionStart =
+		new MxNextActionDataStart(p_action->GetObjectId(), p_action->GetUnknown24(), p_val);
+	if (dataActionStart == NULL) {
+		return FAILURE;
+	}
+	// TODO: insert dataActionStart to a list
+	return FAILURE;
+}
+
 // OFFSET: LEGO1 0x100b9420
 MxResult MxStreamController::vtable0x28()
 {
 	return SUCCESS;
 }
 
-// OFFSET: LEGO1 0x100c1c10 STUB
+// OFFSET: LEGO1 0x100c1c10
 MxResult MxStreamController::vtable0x2c(MxDSAction* p_action, MxU32 p_bufferval)
 {
-	return FAILURE;
+	MxAutoLocker locker(&m_criticalSection);
+	if (FUN_100c1a00(p_action, p_bufferval) != SUCCESS) {
+		return FAILURE;
+	}
+	return FUN_100c1800(p_action, (p_bufferval / m_provider->GetFileSize()) * m_provider->GetFileSize());
 }
 
 // OFFSET: LEGO1 0x100c1ce0 STUB
@@ -91,3 +110,9 @@ MxResult MxStreamController::vtable0x30(undefined4 p_unknown)
 {
 	return FAILURE;
 }
+
+// OFFSET: LEGO1 0x100c1a00 STUB
+MxResult MxStreamController::FUN_100c1a00(MxDSAction* p_action, MxU32 p_bufferval)
+{
+	return FAILURE;
+}
diff --git a/LEGO1/mxstreamcontroller.h b/LEGO1/mxstreamcontroller.h
index 4bee2f4c..6422d12d 100644
--- a/LEGO1/mxstreamcontroller.h
+++ b/LEGO1/mxstreamcontroller.h
@@ -35,11 +35,13 @@ class MxStreamController : public MxCore {
 	virtual MxResult vtable0x1C(undefined4 p_unknown, undefined4 p_unknown2); // vtable+0x1c
 	virtual MxResult vtable0x20(MxDSAction* p_action);                        // vtable+0x20
 	virtual MxResult vtable0x24(undefined4 p_unknown);                        // vtable+0x24
-	virtual MxResult vtable0x28();                                            // vtable+0x28
-	virtual MxResult vtable0x2c(MxDSAction* p_action, MxU32 p_bufferval);     // vtable+0x2c
-	virtual MxResult vtable0x30(undefined4 p_unknown);                        // vtable+0x30
+	MxResult FUN_100c1800(MxDSAction* p_action, MxU32 p_val);
+	virtual MxResult vtable0x28();                                        // vtable+0x28
+	virtual MxResult vtable0x2c(MxDSAction* p_action, MxU32 p_bufferval); // vtable+0x2c
+	virtual MxResult vtable0x30(undefined4 p_unknown);                    // vtable+0x30
 
 	MxBool FUN_100c20d0(MxDSObject& p_obj);
+	MxResult FUN_100c1a00(MxDSAction* p_action, MxU32 p_bufferval);
 
 	inline MxAtomId& GetAtom() { return atom; };