Yeah, sadly there's not really much chance of getting the file names changed on BBT. There are a few things you can do to try and make organising them easier though; for example, you can use the Windows
subst command to create a virtual drive (in other words, if your videos were downloaded to, say, C:\Users\you\Documents\Bittorrent Downloads\stupid long release name\filename.mkv", you can use substitute to create a virtual drive (with any letter you like), which redirects to that folder. So you could access it with the path "I:\filename.mkv" instead of the original, for example. Quite handy in cases like this). You can also use symbolic links (google them) to achieve a similar effect.
In an ideal world BakaBT would implement a rule that ridiculously long filenames have to be shortened, but I can't see that being likely to happen any time soon (although it would be nice if it did). In an even more ideal world, release groups wouldn't be retarded enough to name files like that in the first place, but frankly, that's even less likely.