I am trying to crack Muzicman 3.5 Build 808 and am having serious problems. I have cracked the previous versions after quite alot of hard work but this one has changed alot and I can't find part of the code I need. I am aiming for first a nasty byte patch then I will see if I can keygen it. I've looked at it with IDA, TRW2000 and dede 2.5. I can get the unregistered text part of the splash to disappear [whoopi ] and also the nag on start-up but this is merely cosmetic. Some how I lose myself in the code after tracing it for a while... well to make a long story short I am stuck. I suspect there is some checksum involved as changing certain bytes result in really strange errors (but then again maybe I just patched the wrong place).
B.t.w the UPX isn't a problem as I unpacked it first. So if someone could have a look and give me some suggestions on how to proceed I would appreciate it greatly.

// SuperCali

Just though I'd clarify the protection a bit. It's a serial number stored (I guess for now because I haven't verified it yet) in a file. There is a registration input dialog under settings menu, but it never displays a message if your code is wrong (not sure, but I don't think it displays a message even if the right code is entered). The protection itself is a 400 file limit on the amount of files in your mp3 collection.