Called right before the cut-scene code is called.
This function is responsible for changing the input state and pausing any global threads. 
 It is very important that the input stack matches when the cut-scene ends.  You can turn the cursor/input on and off during a cut-scene, but if you do a 
INPUT_PUSH be sure you do a matching 
INPUT_POP before the end. 
 Starting a Yack conversation in a 
cutscene is OK, but it needs to end before the 
cutscene ends.  If a 
cutscene is started in a Yack conversation, the Yack converation will abruptly end.  If an override is triggered during a Yack conversation in a 
cutscene the Yack will be abruptly end.