I am trying audacity 1.3.3 beta and I realized that when I export a wave into mp3 using the suggested lame encoder, small empty trails are added at both extremes of the wave. This is a problem, since I wanted to create a music cd, in which a full long song would be segmented into 10 tracks, and I wanted to listen them without "cuts" (I mean, the burner was set to burn without the 2 seconds gap). The problem is that the exported mp3 files had those small empty holes and that made very noticeable the track change. This doesn't happen if I save the wave as wav format.
Also I have realized that there are problems with the progress dialog when I have more than 1 instance of audacity importing/exporting simultaneously. The dialogs get freezed, despite the fact the read/write operations are properly done.