Yeah, PTY was quite fun experiment but it's basically a one big hack on another big hack powered by a third hack . Forcing sublime to do things it was never meant to do:
There were three main problems:
1) pushing changes on screen was a tiny bit too slow for it to be usable, it "worked" in tech-demo kind of way, but after a few minutes you would just get frustrated with it
2) I was torn between developing windows version (for my day to day work) and linux/osx one (for my hobby projects).
3) Sublime added ugly pinkish border around regions, making final output not really that pleasant to look at.
Since then 3 and 2 have changed somewhat. My new workplace is 100% POSIX compatible and Jon improved region drawing a bit. Also new async API in ST3 could make it easier to fix point 1.
I'll probably try to revive this project soon and see what happens.