This has only happened since the new update released. Everytime I play a battle in my Imperial Campaign, I get to "an random" point and the PC just shuts down and restarts!

Any similar issues with the new update? NTW was totally stable before, I've played several campaigns pre-update with NO issues at all.

Firstly, no, I have exhaustively tested this by using different saved campaigns etc. Two options occur to me...

1) start a new campaign game from scratch in case pre-update save files aren't compatible.

2) roll the game back to pre-update, though I'm not sure how to do this with STEAM.