MacOS GSB crashes when i attempt challenge

hey folks

i downloaded the mac os x bundle verion of GSB from Steam and everytime i go to try a challenge, the whole game crashes. thoughts?

Have tried doing really old challenges? I have that happen when I try any recent challenges, but old ones seem to work just fine.

On Mac OS X from the App Store. I’ve won all the scenarios, but my Challenge button is never activated. Do I have to unlock all the ships and mods too?