Hi c-major
The exported avi was fine. I export from 3.79 as version 3.89 has this option inactivated for me, but I am using it for evaluation.
The editing in version 3.79 was as expected...I could grab the audio track and drag it into synch with the audio of the main clip, and although it didn't move along with the cursor, it remained visible and the same size. It moved to the cursor position when released. So it was OK.
In version 3.89, clicking the soundtrack to grab it reduced it virtually to a line, so removing the peak which had been grabbed. (looked like it was instantly zoomed in to a different point in the track) Although you could drag it (apparently) it was not particularly accurate. Also the red cursor line jumped about. (Which may have been due to the fact that both tracks had their speed altered a few percent to make them absolutely the same duration.
Here are two screenshots from 3.89. The first is the normal soundtrack with piano chords on Audio Track 2 visible before clicking and the second shot is the appearence when one of the peaks is clicked prior to dragging
. 
Although the cursor is not shown, this is the Audio track appearence when the track is clicked for grabbhing.
The peaks have disappeared...
Nat