As it sounds like you worked out, that error means it's not finding the soundfile. A lot of times this happens due to a mangled name. Zip extraction likes to mangle non-native character sets, so if you're on a non-english system it might be screwing up the title. Other than that, not sure though. I'd try extracting on a different drive: weird shit happens with stuff on system drives sometimes.
The new NW thing can be safely ignored. It's just saying that because you have a newer version of that framework installed on your system (says the same for me). Should still run fine (Though it's obnoxious and I should probably look into silencing it somehow if possible.
Let me know if you have any luck though, and I'll keep an eye out in case this is more wide-spread. So far in beta testing this didn't come up at all, so it seems like a somewhat niche issue.