When I switch drum kits, when I switch folders, pretty much whenever I do anything. It eventually starts to respond but it’s annoying.
I’ve observed the same behavior. The developers are aware of this.
Only thing I can suggest is that you save a new song or drum set edit immediately upon creating or editing. It seems to lessen the BBM performance slow down.
Any Update regarding this issue. I run version 1.65 and the app sometime does not respond for 10 minutes or longer. Sometimes I have to close the App and wait for it to load up. Also getting into Editing midi also is painfully slow. Changing Drumkits while in midi editing almost always causes a hang.