Good evening:
let’s go in order, one problem at a time 
1 - I’ve created a song, and I’ve inserted the audio tracks (I’ve tried both in aif and wave format but nothing changes). The audio tracks were prepared with cubase pro 12. I either used the export vst live command or manually loaded the tracks into the VST-LIVE song.
So far so good.
When I play the song it happens (for no apparent reason) that the audio tracks literally disappear from the song window. Randomly without any logic. I reinsert the missing track… and after a few times that I play the song another random one disappears.
2 - after many attempts I manage to finish the song by adding the parts to define the song, intro, verse, chorus etc… Save the project. I add a second SONG to the project and do the same things I did in song n1. i.e.
I insert the tracks, lyrics, chords, etc… I define the parts. I finish. I SAVE the project again… I try everything summarily. it seems to work. The next day I reopen the project and I find myself with: Song 1: audio tracks work, there are still lyrics and chord tracks… but without the contents. all lost. no lyrics no chords.
- Song 2: Basically everything is there… except audio tracks and lyric and chord content. There are only colored trace lines but no waveform. in fact it doesn’t play anything. Two days of useless work.
- I tried to open the module with VstViewer but it gives me a message that the license was not found. I don’t know what to do… I tried to follow the directions he gave me but it didn’t help.
My computer is a macbook pro with intel Core i7 dual-core 3ghz 8gb 1600mhz DD3 - ssd 750gb MacOC Catalina ( 10.15.7) I also installed vstlive version 1.1.43.664 but everything as above.