Hi!
Thanks for your suggestion, but I have actually solved it already, this way:
Each one of the shows were made (with correct BPM respectively) and saved as different cues on the workspace. Each cue was then exported (File -> Export cue) to the computer as qsbframes, adjusting the setting to Timebased (important!). These are now like animations (without sound). After that, I imported the files again to empty cues on the workspace (right click on cue -> import). (That part can probably be skipped as you can also open the file from the computer later.)
On the time line, I opened the first audio file from the meny, then placed the cursor after the track, right clicked -> Create new event, and chose the next track. I then created new, empty events below each track and adjuted the size of the events (important!) to exactly match the sound tracks. After that, just drag the desired qsbframes cues from workspace (alternatively right click -> open, to add the file from the computer). Adjust if needed, and when all tracks and animations are in the correct positions, just save it as 1 cue on the workspace. Tada, -you now have 1 show with as many tracks as you like and all beams/animations are in perfect sync to the music!