I don't see why not. You could sell add-ons for blitzmax that require blitzmax so long as you don't sell blitzmax along with it.
Game Mods - Can You Sell A Mod...
Miscellaneous Forums/General Discussion/Game Mods - Can You Sell A Mod...The forum is locked. These are the original blitzbasic.com forums, kept so they can still be read. No new topics, replies or edits can be made here. To join in, head over to the Blitz3D+ forums.