I'm in the same situation. It looks really promising, and I've managed to sort out the other issues to the point that it seems to be running correctly on the server, but I've pretty much hit a brick wall with the OpenID provider, as there no longer seem to be any sites supporting OpenID, and all related server software projects seem to be abandoned since the late 2000s.
Basically, it seems as if OpenID is universally considered deprecated.
Is work being done to support an alternative method of authentication?