Game Maker Sonic Engines

[TheomanZero]

I lurk on Sonic Retro fairly often, and recently I came upon a topic dedicated to discussing Sonic engines for Game Maker.  Since Fusion Fangaming is largely Game Maker-based, I thought it might be worthwhile to link the thread here, in case anyone is trying to make a Sonic game or something similar:
http://forums.sonicretro.org/index.php?showtopic=24554
Note that I did not make any of these; I'm just linking to them because I thought they'd be helpful.
Incidentally, I remember that a while back, MKF was looking at a Game Maker Sonic engine to make the World 7 levels more accurate.  It's possible that this isn't relevant any more, but if any of these engines can help MKF (even if just by reading the code for ideas), then please look here.