I was able to download the PBDraft.rkf file from Wolverine Studios, but I have no idea how to open it. I installed Open Office, but it doesn't seem to be able to open .rkf files. Or at least I have no idea how to make it open it.

How do you open the .rkf and edit it?

Where did you download it from? If you downloaded a version that was meant from 2019 and before it is not going to work. Otherwise the database formats are now in SQLite format - you can download that for free and use it to edit the database

I downloaded it from https://wolverinestudios.freshdesk.com/ ... class-file. Where's the updated version for 2020/2021?