EMI Demo: Fix a segfault, allow the user to skip the intro movie, fix attached actor placement

When you press F1 during the intro movie, then ESC to return, the EMI-Demo segfaults. This patch fixes that segfault by adding support for the registry. These functions appear to be leftovers from Grim that remain in the Demo.

The second change allows the user to skip the intro movie by pressing ESC. It works on the original engine, but not here. I haven't figured out if there's an error in the scripts, but I'm not seeing a way to skip it. This hack lets us skip the movie anyway.

The third patch fixes attached actor placement. In the original engine, it appears that attaching does not change the value returned by getpos(), only getglobalpos(). Removing this line prevents the attached object from being moved twice. This fixes the lights in the Governor's Mansion Interior.