The repo right now is basically a massive PoC and probably isn't useful until it becomes a CLI.
I've tidied much of the PoC up but I haven't enabled downloads yet.
Overview
Humble has a lot of trouble with larger libraries on all platforms. Sidestepping its constraints is fairly easy thanks to Hayden Schiff and his great writeup on reverse-engineering the mobile app. In the two years since that was published, there have been a few API changes that have to be taken into account, but nothing too hard to figure out.