Do the latter, i.e. the thing you mentioned last: just put the KUAL-...-2.0.azw2 in your /documents folder. Wait a bit to let your Kindle find this document and add it to its list. Open this "book" - you'll find yourself in the KUAL Menu. Don't bother about MRPI - this is simply not necessary for PW2 and even PW3.
Gesendet von meinem Google Pixel mit Yabba-Dabba-Talk.