I appear to have solved it, seems to have been a problem with the blueprints library. The game was crashing every time I saved in game or restarted a new game. After deleting the blueprints file it no longer crashes, seems to be working fine now.

My game freezes, then crashes once I alt-tab and alt-tab back every time I exit the game. I have uninstalled all mods, and re-installed the game. The same crash happened when I ran the game on vanilla, then again once I ran it on the latest experimental beta, still with not mods installed. I haven't ...