I've been having issues today in the Mechlab...
The first time, when I finished my build and tried to launch, it had the red triangle saying the build was wrong... when I looked at it, it looked like somehow, the STD320 engine i had there disappeared, but the 2 heatsinks that go in it were still in the center torso... when I removed both heatsinks, the engine suddenly reappeared with both heatsinks, the build was fine, i could go to checkout, and launch my next game...
An hour later, I'm again getting the red triangle, although there is nothing wrong with the build, and it shows the STD320 engine correctly... but now, although it allows me to remove equipment (not engine), the tonnage doesn't free up (still shows 95 of 95 tons in my Banshee)... but when I try to remove the engine, the game freezes...
I tried restarting the game, but it won't let me use or fix that mech... I haven't tried others mechs, but I assume they work? will try them now and see...