Thanks for getting back. Unfortunately i found that there was no ability to select “Keymaster” role from the top left flydown as you mentioned.
I did find a very easy fix though on another forum and when i tried it, it was simple and quick.
Go to Plugins > bbpress > settings > change default for forums to Keymaster (save) > go back to users and assign anyone you want to be Keymaster. (save) [anyone who had a previous assigned role to forums retains that role. It didn’t change any prevously assigned roles for members]. > once assigned, go back to Plugins > bbpress > setting > reset your default for forums for members back to whatever it was.