This unofficial project ports back most of Sonic Unleashed's day levels from the Xbox 360 version into Sonic Generations on PC. It also includes any improvements that are deemed as necessary to accomodate to the better control scheme, higher resolution..
Apparently you can play Unleashed-style levels using mods.I don't know what SEGA looks to in deciding what gets made or ported, but I'm definitely pissed that they didn't allow Christian Whitehead to work on the Sonic 3 & Knuckles game for Android. And the PC ports of the classic ...
It's not Sonic Unleashed on PC and it never will be. There's no reason to port trivial fluff where it doesn't make sense, like cutscenes, bosses, sequences, etc. Sega's the only one that can release Sonic Unleashed officially on PC. This is simply a total conversion mod...