I'm not sure I understand how you're attempting to create the CD layouts. I assume you're using the wizard, or choosing "Audio CD" from the menu.

Then it sounds like you're dragging a folder of MP3's onto the layout pane. I don't think you can drop folders of files that way. You should just open the folder and drag over the files you want. If that isn't working for data CDs, that's a different problem.

The other problem may be that Nero just doesn't like burning MP3s. A friend of mine was shocked to learn that I convert all my MP3s to WAV before I burn them. I just don't want anything to screw up the process. Unfortunately, Winamp's output plugin for this purpose seems to change the files slightly, raising the high end. If anyone knows about this or how to fix it, let me know.

I'm trying to burn a CD using the same process I think you're using, so I'll see how it works. If it doesn't, I've got more CDs. If it does, I'll have a nice copy of Pearl Jam's Vs to give someone