Okay... according to the bugtesting .cap that I originally sent to David, the fixes that he made are all in 84 (and - embarassingly enough - 83 as well), except that the falling through platforms thing is still there. It doesn't happen all the time in the tester .cap I sent him (it still does occasionally), but it happens a lot more frequently in my Platform School .cap for some reason.
http://dl.dropbox.com/u/529356/platform ... ground.cap
So... yeah. I guess I was wrong, and the fixes are there. It's just that the one I checked for in Platform School is still around, but mostly just in Platform School. I don't know what's up, I guess I'll have to do some more testing.
As for Porlo, try recreating that .62 bug from scratch in .83 or .84 and see if it's still there, I'm not experiencing that bug at all. It could just be a backwards compatibility issue.