Painter Brushes Ultimate Pack : bought externally, downloaded .exe file, opened with 7-Zip and that's as far as I get

(Sent this yesterday in the chat of the Corel FB page as there were suggestions that this page's responsive : "Hey guys, just bought the Painter brushes ultimate pack, but it doesn't show up in the brushes categories and , as I checked on the net, a lot of people are having trouble getting this to work or even to locate it. It doesn't show in the APP/roaming folder either. Some suggested buying it again from within the program and asking for a refund for the "outside "purchase, which went through Cleverbridge . Hope you can help me out - installing Painter 2021 took some distant assistance from Canada-Corel, I hope this time it's a bit more easy going".)

update: Ok today I've been able to trace the folder "PainterUltimateBrushPackBundle" by opening the .exe file with 7-Zip; opening that, I get an .rsrc folder, a .data item, .rsc_1  and a few others That's as far as I get now -

How do I get the brushes to show up in the Brushes menu in Painter 2021?