I’m not sure if you saw the tutorials - but it really makes the work flow clear. Do I think it’s necessarily the easiest, most logical work flow? Not really. But it’s not brutal and perfectly workable once you see the procedure once or twice.
There are two that are crucial. If you miss the ‘export/import’ procedure? You’ll founder on your own.
(yes - it’s for Win7, but it pretty much applies to Mac as well) This is where you import all the necessary midi files and drumkits that you’ll need to work with. Think of this as ‘loading your toolbox’.
This is where you really learn to navigate through the folders; export/import basic songs and rhythms; and get creative in thinking of ways to amend and adapt the ‘canned’ songs to suit your requirements in specific songs. You can pull different rhythms and sounds from various sources to create ‘songs’ that you can work with - but you’ll have to grasp the notion of looping sequences and the concept of butting and splicing ‘split’ regions of Garageband and Cubase (and others) together to create a cohesive song start-to-finish.
If you’re not comfy with Garageband or Cubase or similar softwares…it’d be a really good idea to do so. The workflow and ‘look’ of the software is similar. Not entirely identical, but close enough that a reasonably good comfort level in them will transfer nicely to BBMgr.