@sallyanne- short on bandwidth? so no video
Make / add a gimpressionist brush? - got you mixed up with pat625 - don't know why.
(1) Check in your Gimp profile gimpressionist folder that a
Brushes folder actually exists. If not make one.
(2) In Gimp create the brush, grayscale, white-on-black seems favourite.
(3) Open a new canvas so that your brush is not active
(4) Open gimpressionist. (5) select your brush from the drop-down select menu (6) Save-As
(7) Make sure the Brushes folder is found. (8) Give the brush a name ...and Save
(9) Your brush shows in the brushes list, set up sizes etc and OK.
There is a collection of brushes/presets on this page
https://gimpchat.com/viewtopic.php?f=12&t=7818