My guess is it's the hacked syssetup.dll causing the problem. Try without that. I'm going to do a quick test on my own and see what I can reproduce. If there's bad files, I'll remove them until I get ahold of working ones. EDIT: Just integrated all 4 and haven't seen any problems. What stage of Windows setup are you seeing the errors at? I've made it to T33 with all of them and no issues (and I seem to remember fatal signature errors happening pretty much immediately at the beginning of GUI setup, like at T39) EDIT2: I've got a couple hotfixes showing as needing to be reinstalled according to qfecheck, but that's to be expected when using hacked files. EDIT3: Hmm, apparently I didn't copy syssetup.dll into i386 properly . I'm building a new ISO now. I'll get back to you.