I don't understand why, but somehow creating a new user solved the problem. Not only did Wow.exe work right away (provided I use the -opengl flag) but it also did so with sound. You might blame me for not trying this sooner but I do want to point out that I did remove the entire .wine directory, and all related files - for the rest my regular user has only been in use for a few weeks so I didn't think it was that messed up yet. One thing I did notice is that the new user account has some strange graphics settings, it doesn't look as sharp/good as under my normal user account, as if different graphics settings are used. When I find out more about this I will report. Another thing was that WoW asked me again for acceptance of the EULA etc, something which it did not do when I ran it as root.
