Asking for money is such a sensitive topic, but as a person who tried to make several mods myself, I must admit that it’s rather difficult and very time-consuming. In my honest opinion, if the overall quality and the Jbeam are on the better side, it shouldn’t be a problem to ask for money. However, I also think there should’ve been a lite version for everyone to enjoy. This mod looks good, and I might try it out in the future!
ror doesn't have any lua integration, it uses angelscript (which is similar to c++) and the ability to add scripts to vehicles only got added recently iirc