My MDD is temporarily offline for repairs, but the highest I have used was 10.4.11. It works great! As I recall, there were only a couple of features which didn't work, and they were ones I never typically used. Maybe the CD burning utility? Anyway it opens, edits, and saves files perfectly well. The FX Machine and Sonic Destructor work fine too. It is my fave stereo editor, with Amadeus being a close second. It's really a shame that TC dropped everything to persue PowerCore exclusively.

There are two patches which I am aware of. The patch you are referring to was an official release for 10.3, and then some of the original coders wrote an unofficial patch for 10.4. They were both hosted on the TC website but I imagine they are long since buried on there. I also have a 2.8 beta they gave me shortly before it went EOL. Never tried the 10.4 patch in 10.5, because I don't run 10.5 yet. I am not expecting them to patch it for intel architectures or 64-bit, so my setup is probably frozen. But I love it.