I'm also experiencing this issue, started with Alpha 12 v 86. No problems with designing the ship, then upon launching to battle it freezes. Doesn't happen all the time. Many times I'll have programs open in the background, Firefox, Chrome, OBS studio and I'm thinking its a certain webpage (YouTube) that might, might, be causing this for me. But it was something which I noticed upon the update for Alpha 12 that I didn't have happen before.
I've got Intel(R) Core(TM) i5-4590 CPU @ 3.30GHz.