Hi, I report as required the .vlprj file that I used during my test:
Test_02.zip (203.2 KB)
The two songs initially appear as in the screenshots below:
After passing a few times between the two songs through the Setlist menu on the left of the application GUI, simply passing the mouse (without any click) on the events present in the audio tracks resulted in the following situation:
Notice the track events for which the lengths are set to zero.
I remain available for any further information on this software behavior that I have encountered.
Thank you for all the support provided.