Is it just me?
Unable to downsize the Manual Cache Size, originally had the Manual cache set to 100 gig, but didn’t need that much space so decided to change it to 10 gig. In the cache window changed it to 10 gig , hit enter and original 100 came back. Unable to decrease the cache at all.
Increasing the cache size was ok, but not make it smaller.
Had to delete the cache through the file system.
Submitted a Bug Report to the Zen desk
Why are you even bothering? Manual cache doesn’t even work.
like it is supposed to be, u can only increase the size.
only workaround: delete it manually via explorer and start from scratch 
however, since it is boken anyway why bother? just forget about it …