I have not had any problems with Unity.
I need to work on making the code more open to custom classes, but I am focusing on other things at the moment. I can create an extension that allows some customization, but I don’t think I’m allowed to share the data file from the ruleset.
To clarify, this is for auto-filling the character sheet when you gain a level. You can create custom classes now and manually update the character sheet when you level up.