It sounds like you may have purchased two incompatible marketplace items. The module has everything, monsters, maps, text, art, etc. The add on is for people who only want the maps, and art assets. Fro the Addon's marketplace page: Important Notice: The Waterdeep: Dungeon of the Mad Mage - Map & Card Deck Addon is not designed to be added into the core Dungeon of the Mad Mage adventure module, as these elements already exist within the module. Attempting to import them into the core module will result in your current maps being overwritten by the addon's maps. If you have indeed purchased both in error, don't worry. Just contact <a href="mailto:team@roll20.net" rel="nofollow">team@roll20.net</a> and they can probably sort you out quickly. This double purchase happens from time-to-time.