That’s interesting...I know that when at college or university anything you create on their ‘clock’ they own or get a share of....no idea if that applies to the arts....but in engineering had you written code or invented a process or product using their kit or on their time, they got a share. It’s why many genius inventors invariably do things in their ‘dorm’ or people at work are at pains to say they did it after work or in weekends. @lowandslow If they’ve credited you, and aren’t trying to alter or claim you original material, what exactly do you want? Financial recompense or something else?
I guess finding you to ask might have been an issue....completely agree it would have been nice to have been asked plus they missed some additional sales!