Played through most of the game (All except Teeth of Naros, omw)using the steam trainer. Most of the functions work except inventory related items (super, unlimited, and multiplier) Don't use XP however until you get past The coming storm in the main quest, as it can bug the main quest and make it impassable. No actually the trainer as it as to do with side quests so just focus on main quest until past that point. the ability points and skill points works however so you don't have to use the xp anyway though I did wait until I completed those quests. Just easy kill until then. Using Windows 8 64bit with Steam.
Update: on a whim during Naros I tested super inventory again and it worked. Will use on replay so I don't need stash. (no stash in Naros)