I'm loving Force Unleashed; I haven't really run into any bugs for the most part.
Except this one: I unlocked a new costume near the end of the second planet, it's the Sith Robes, which makes Starkiller look very cool. Since he looked so damn cool in them, I put them on for the rest of the level. The next level, they're gone and locked back up again. I did a quick look on the forums here, and sure enough, several others have run into the same issue; we all got it legitimately, and all of us lost it because we put it on "too early". Some are making it sound like if you play it over again, you can re-unlock it; no one has actually said they have it though. I worry that since the game should have already registered me getting that holocron, that it won't be there a second time. I really hope that's not the case...
Oh, btw, apparently "suck" is a curse word. Hide the children.
Edit: I saw another post that said you could go back and get it, so I did and now it's unlocked. Weird how the setup is, that you kind of have to wait until the next level to put it on for fear of losing it. Technically, it should work if you get it then get an auto save soon after. Regular saving doesn't seem to do it. I dunno, it's easier to just wait for the next level. :P