Game hangs on map load [mac]

[veryOK]

Ok, so I have combined all 6 chemicals and separated Clarence from my body. I run out the door into the main compound and the cinematic plays. as my screen goes from white to black to load into a new map, the game hangs usually half way through the process.

At this point I can't Cmd + Tab, nor quit the game without restarting my computer. Music still plays, but it seems like the graphics have frozen completely.

thanks, help is appreciated. even a save file set at a later point would solve my problem, i think.