Ha no problem!
I've just had another go at setting it off and I think I've narrowed it down a little: if I equip the corvettes with nothing but the fixed phaser (same as the Finch in the default db) then it doesn't happen, but anything else, like machine guns or whatever, and I get the same crash:
[GAME VER] 0.8.16_UPDATE_7.1 - KIRK
[CLOSED BUILD] False
[CPU] 8 x Intel(R) Core(TM) i7-4700HQ CPU @ 2.40GHz
[OS] Windows 8.1 (6.3.0) 64bit
[GPU] Intel(R) HD Graphics 4600
UnityException: Transform child out of bounds
EDIT: Right I've done some more playing around with it and I think it might only be the machine guns that are causing it to crash. I've tried a mix of energy weapons on all the corvettes and they launch fine, but anything with a fixed-med machine gun equipped triggers the crash. Happens with all the corvette hulls, whether they have anything else equipped or not.