1) What software version are using? The latest is 4.0.1.441, so if your version is older, you should get the latest one here:
http://www.djsoft.net/enu/update.htm2) About INI folders, all settings are stored in the Windows Application Data, but you shouldn't modify any files by yourself.
3) With WAV files, it's a bug, and it'll be fixed very soon (within 3-4 days).
4) If MIC button and Line.In are setup to use the same audio card, and same input, turning on MIC and then turning on/off Line.IN will cause the MIC to also stop working. This is a driver issue and we're currently worknig on solution.
5) To use playlist generator, first of all, add tracks to the Music Library (and save it). Then, start playlist generator, click the "Clear" button, and click "Generate" - this should generate playlist with 1 track. Then, start to set your own parameters. It should work.
6) About Exception, when/where do you get this message?
Thank you!