To be honest, I actually spent more time in Crerar than Reg. I did enjoy my time taking nap on the fifth floor of Reg at the East Asian Collection. On the sofa by the window I would find a perfect view of the campus and especially of Cobb Gate and Harper Library. Perfect place to doze off after a big lunch ;). And the East Asian Collection was usually much quieter than the hustle and bustle on the lower floors of Reg.
I remember the creepy guy at the exit squeezing my bag every time to make sure I wasn’t making off with a rare collection of anything, the coffee shop on A level, and the time I got locked in with lights out when the Reg closed up early once w/o my being aware - and getting scolded by the janitor for hanging around after hours. I was just glad to get out of there alive! I don’t think they squeezed my bag that time. Edit to add: that would have been the perfect time to make off with the rare books collection.