I don't know Mac systems at all but Dorsai is probably correct. I believe the VG software works more or less in the same way for Mac and Windows. Chances are that Dyamaka has the 'models' folder twice in the file path. I once accidentally added the models to a NEW models folder on my external drive. I then ***** the same problem :/
On my ext drive, the pathway looks like this: My Computer > E: > Vgirls > models
When I added the extra models folder, it looked like this: My Computer > E: > Vgirls > models > models.
Then, obviously, the software couldn't find the models files. The software is only looking for the 1st models folder, NOT the 2nd :(