Some more info: the menu is the problem here. The menu background is a 2.5 second movie tht is just a 1 sec fade up on a title card. There is one button, which is an 8x8 graphic that sits in the top left corner (i.e., "invisible" button). This button links to the 1 timeline, which has an end action of returning to the menu. There is also a fade out movie that is the button transition. When I remove the fade in menu background, the build will complete, so this seems to be the problem. Screenshots of relevant tabs attached.
