Without the template information you were asked for, including data from "ulx version" and lua errors appearing in your server console, we find it difficult to really help you with a 3rd party addon.
Even if we could help, it's more than likely going to rely on the 3rd party devs modifying their code to work with our new system.
That being said, I've perused our code.
We still use ULib functions to call both standard gmod and non standard additional data storage for ban.
Those names haven't changed, even if the code inside them did a bit.
It likely still not going to be anything we can do.