RunConsoleCommand is a CLTClient member function, so either call it from the class or reference it directly with a function pointer, as such:
i don't know why you are passing the integer....
typedef VOID (WINAPIV *tRunConsoleCommand) (const char *);
tRunConsoleCommand RunConsoleCommand = (tRunConsoleCommand) 0x490610 //RunConsoleCommand address (Why do people call it LTClientEXE?)
//And how to call it
EDIT: It also depends what commands you are running from RCC, IIRC if you call NoFog then you will crash. What commands are you passing to RCC?