not trying to be negative here as I would like tv-out as much as the rest of us. But....
most of this has been tried over at XDA (I still say try it if you want to though, as you may do something different/better)
http://forum.xda-developers.com/showthread.php?t=412350
is the main thread. page 11/12 talks about the same registy keys as mentioned about, and then onward talks about swapping out that dll with the touch pro's, with some bad results.....
anyhow I would say give it a read before trying at least.