Hi David,
I love Hogwarts RPG and would like to write a setting for another school in the wizarding world based on it / making use of the rules. Would it be ok with you, if I adapt your rules accordingly or maybe I can even treat it as a Hogwarts RPG hack of sorts? Let me know, what you think. Thanks!
Hey there, glad you like the game! All of the original (non-Harry Potter) content in the game is released under a CC Sharealike license. That means you're free to hack, modify, or reuse the game text & rules as you'd like, as long as you provide credit and release under the same license. No permission needed
In short, go for it. Excited to see what you make!
In the end, I created this: https://rootdwarf.itch.io/castelobruxo-rpg I made sure to credit you and your inspiring work and should someone be done with exploring Hogwarts, maybe they feel the call of Castelobruxo.