Making Someone Else the DM

Is there a way for User A to create a game and then transfer GM control to User B? Or, if User A has purchased module X on Roll20, is there a way to allow User B to create and DM a game using module X purchased and owned by User A.  My situation is that one of the players in one of my regular live groups has purchased a module on Roll20, but doesn't know Roll20 well and has asked if I would run it for us?  Any suggestions on how to do this?

Whoever created the game can promote someone else in the game to GM.  The module, addons, and perks that the game will run under will be determined by the game creator.