When I render an MP3, all of my audio gets shifted right by 0.028 seconds, while my region markers stay the same. This only happens when I export MP3. I tried WAV and OGG, and they rendered correctly.
As far as your regions and markers, try pre-shifting them to the right before you render.
There are some utilities on the internet that claim to remove or encode without the gap, apparently with varying degrees of success. I haven't tried them.
"I'd be curious to know what the application is for an MP3 where any factor is at all critical.. Not be facecous, just curious...."
Geoff,
The only "critical" situations I can think of would be looping for an Acid-like application, or ringtones, or in a music video, where cuts have to be precise. In either case, it is beyond me why anyone would use MP3 in such a situation. Just a beginner's presumption, afaiac. BTW, that is the most creative spelling of "facetious" I have seen.
;?)