#1 is resolved, this was a really dumb error caused by sloppy importing of legacy code. Mostly it comes down to the old server config using a URL to point to a file, where it should have been using a path to the file on the disk. Before, it didn't matter because the old path joining code sucked.
#3 appears to have magically fixed itself, mostly. Capcodes and #fortune aren't working, but that's not much of a loss.
So that's two down, two to go, and all critical posting-related problems seem to be resolved. Woohoo!

>>3
BBCode is a mental disease, much like Pascal.
I was, however, thinking about some sort of lispish markup just for /code/:

(b (i (u (o hello))))