Found an interesting bug of sorts. If you play a file from a cd or dvd and then change it to play the same file on the hdd and eject the disc, Xion throws up a file not found dialog if you try to close it. This doen't seem to happen with usb drives.
For this to occur Xion has to be launchedby opening the file eithwer in explorer or by adding it to a clean playlist. The dialog box says Shimmer: Xion.exe - No Disk on it