Based on the 24XX SRD from Pretendo Games,  there's now a free, standalone Barrow Keep  playkit with all the rules you need to play! If you've been hoping there would be some simple, standalone rules for Barrow Keep, you can find them on that Itch page. They're currently still in playtest format, but you can grab them (along with the two sample adventures) for free. The beta playkit includes six playbooks and rules for using them in play, as well as the two sample adventures.

I've always planned to release further issues of Barrow Keep, but wanted to be able to spend more time on the setting and less time on system playkits. Having this set of houserules should assist with that.

Enjoy!

Richard