OR blocks are one of the most complex parts of the event engine, since the way the picking works differently has ramifications for the entire way all picking works throughout the event system. Given that many conditions internally work differently with their own particular algorithms, it can result in some pretty difficult edge cases, which is what I suspect is going on here.
Currently we are still very busy with the C3 beta running up to the full launch, C2 is pending a stable release, C2 is only in maintenance mode, and this bug report is only a few days old. I can't give an ETA when I'll be able to investigate/fix this or any other related issues, but hopefully I'll get to it at some point.