I had a lot of reboots involved, and still don’t quite know how I got it to finally work. My best guess, however:
Make sure media sharing’s off in WMP11. Uninstall the Zune software if for some reason you actually installed it like Microsoft would desperately prefer people to do.
Get rid of both TVersity and the FFDshow bits. This is just for simplicity’s sake, I’m not saying it’s actually needed.
Reinstall the latest FFDshow. Make sure it’s actually the latest–it’s apparently one of those sourceforge projects with umpty forks, most of which are laughably out of date. I grabbed the clsid build from here. I think I pretty much checked everything on the install.
Reinstall Tversity. Reboot–I don’t think this is necessary to actually get the media server service running, but I had to because the gui was acting downright wonky on me without it.
Fire up the gui for it. Settings tab, set the media playback device to Xbox 360 instead of auto-detect. Under transcoder, set it to ‘always.’ Add whatever folders you’d like to share bits from.
Open up its port in the firewall. What the hell, reboot again.
Now on the 360 side, go the usual video->computer route. When it asks if you’ve installed etc., say yes. It’ll promptly fail to find anything. But at this point, you should be able to tell it to connect to another computer–which is the point at which it finally saw mine.
Now I just have to wait till a new version of TVersity fixes a little problem where video playback cuts off a minute before the end, and pray I can get it working again.
Honestly, there may need to be some sort of santeria-style animal sacrifice in that process, too.