To anyone else willing to log, I also found this pinned topic helpful from GMEvangelos:
It tells you step by step how to turn on enhanced logging in Steam, using the same key that Chesqin gave.
I also encountered the stuck-at-pre-game mode problem yesterday, where it counted down 5,4,3,2,1 and just hung without starting; unfortunately, enhanced logging was not turned on. I’ll try to keep logging on as I play the next few days to see if I can catch one.