If you think you might have purchased something in error and need to make a change, email <a href="mailto:team@roll20.net" rel="nofollow">team@roll20.net</a>. If you want to run Strahd in a different game system, Pat's advice is spot on. If you want to add one or more of the maps to an ongoing game, then yes, you have purchased the module, and you needed the map pack. The good thing is, the map pack is cheaper, and hopefully, you can fix that by contacting the team. If the problem is something else entirely, please describe what is happening and what you would like to have happen in more detail, and one of us can likely point you in the right direction.