It could be that you're facing an overheating problem. A while ago my PC started to shut down after some minutes of gameplay and yeah while I was playing Forgotten Hope after some minutes I could experience several shutdowns.
I don't know what has Op. Cobra have to do with that though, could be that the objects in the map would increase a higher load of textures and 3d figures and therefore get your PC's temperature hotter.
Try to check your PC. I opened my laptop's fan zone once and found it was totally full of dust, I took it out carefully with a vacuum cleaner and I didn't experience any shutdowns anymore and in addition my laptop went to back to its normal temperatures.
