MAINMENU_DisableControlIfDataNonZero returns BOOL, not void
Both exits load 1 after the call to 004f9740: 00430137 CALL 0x004f9740 / 0043013c MOV EAX,1 / 00430141 POP EBP / 00430142 RET 4, and 00430147 CALL 0x004f9740 / 0043014c MOV EAX,1 / 00430151 POP EBP / 00430152 RET 4. It is a menu-form callback reached through the pointer at 0070be58, so the constant TRUE is the handler's result. Return type only. Recompiled with VC8, 00430120 then matches byte for byte.
Changes 1, applied together
Set prototype
win 0x00430120signaturevoid MAINMENU_DisableControlIfDataNonZero(int32_t pControlData)→BOOL MAINMENU_DisableControlIfDataNonZero(int32_t pControlData)convention__stdcall