What you can do, is build-in a license system that checks continously for an active license. If not found the addon will automatically disable itself. The way to build that in and secure so no one can crack it, you have to find out yourself :)
Yes, then probabaly as normal is that this translation is only updated to 2.2.9 and is only compatible with that version. So you have to wait until Mr. Jinx is realeasing a new version :)
All the styles, and template customizations are stored in styles folder right? Otherwise maybe a rewrite rule, to the styles folder of the /club/ or maybe an idea for Xenforo, to make an option to load a style in from a different board and sync them with eachother :)