Not sure if VAM detects references to sounds automatically.
During packing in VAM they should be in the 'Contents ...'-list.
Add them manually if necessary.
Make sure to not use exotic characters in path- and filename.
If VAM fails for whatever reason to pack the sounds:
Use a packer-tool like
7-Zip to open your var-file. Now add your sounds to the VAR manually under
Custom\Sounds\thunder.mp3 for example. I have set VAR-files to be opened with C:\Program Files\7-Zip\7zFM.exe automatically in Windows. That's the GUI.
The actual 'reference' is stored in
yourname.1.var\Saves\scene\yourscene.json.
Extract
yourscene.json and have a look at it with your fav. text editor.
Now you can search for "
Audio" and you should find a section where is stops at "
URLAudioClipManager".
Nearby there is the "
url" : "
reference-path" that you can now verify or edit.
(Note be careful if you decide to change the nearby "displayName" of your sound - it's sort of used as identifier by VAM and all copies of this string must be changed to keep the scene working)
To make the url point inside the var-file it should look like this:
"yourname.1:/Custom/Sounds/thunder.mp3"
Now re-pack
yourscene.json back into the VAR and reload it in VAM to verify it works.