Hi, I have noticed that when clearing the cache in the tools menu, the game always restarts in 32 bit mode. A silly little thing but slightly annoying.
When it asks if you wish to restart the game say No. Then close the Game and restart the 64bit mode as normal Or put a bat file on your desktop to do the job before starting the game Have a read of this - https://steamcommunity.com/app/24010/discussions/3/366298942111524332/ Peter