Hmm, does a character move JUST before the ending? If so, you might be moving one square too far, and getting "stuck". That will actually make it so you can't do anything. To fix this, go into the event where that character Moves, and check the "Ignore Impossible Movement" box. Do this for all Move events.

If that still doesn't work, I might have to see the code myself - if you can zip up your project folder (or make a GameDisk and zip that up), you can either email it to me (bricecube+zelaron /at/ gmail /dot/ com) or attach it to a post here. I'll tell you what I find.