I think it would be nice if "Reset Current Category" would work for brushes that are imported as a category.
When I import brushes and it creates a new category, I think Paintstorm should remember the import filename for that category, and then when I reset the category, it will just reload from that file. Currently (2.10.121117) it gives an error saying "Current Category is not default. Can not reset!".
Maybe when importing a brush category, it could make a copy to the place where Painstorm saves its file (Documents\name\Paintstorm Studio\ on Windows). Then when reloading a brush category, it can load from there instead of random places on the hard drive.
I think the only way I can do it now is to import the brushes a second time, and then delete the old category, which is not optimal.