I've used Debug Tracing more this week as I've been creating more customized, detailed Actions. While doing so, I noticed the tracing results just ended at a point I was expecting an INSERT action. I spent a lot of time checking the Actions on the screen to make sure things seemed good. Finally, I turned debug tracing OFF, then tried the screen again and immediately an error popped up regarding a problem with my table INSERT.
So just a lesson to anyone that might search this forum for debug tracing help...errors are "swallowed up" when debug tracing is ON. So when developing/testing/debugging a screen, be sure to try out your screens with both Debug Tracing ON and OFF in order to get the whole picture.
Hope this helps.