I have a question regarding modules and Co-DMng. I want to buy the Lost Mines of Phandelver module for a friend of mine who is interested into DMng, and help her along the way with it. However, I'm unsure if she will have access to the resources, assets and maps from the module if I buy it, then promote her in a new game, or the other way around. I would really like to see the content I paid for, and it seems unreasonable to me to pay twice for a module that I won't be DMng anytime soon. Any help would be appreciated with this issue, thanks in advance.
Whomever you buy the Module for will have full access to creating Games from that Module. Whomever you promote to co-gm in a Game created with the Module will have the same in-game access to that Module, save for the Game Settings page (which really doesn't have much to do with a Module, aside from possibly setting the right character sheet, but generally you set things in there once and forget about it). Buying a Module does not automatically put all the Game assets in your User Library or Marketplace Library. Those assets will simply exist in a Game you base on the Module. Reusing them will require creating a new Game based on that Module and copy/pasting them as needed. Probably buying the Module for your account and promoting your friend in the Game would be the best option if you want to retain the use of the Module at a later date.
The co-dm also has the choice of being in DM mode or rejoining as a player. Obviously the player would be in player mode and the DM would be in DM mode!
Good point. If you want to not risk seeing anything you shouldn't as owner of the game, you can right click the rejoin as player button in the settings tab and copy the link, then set it as a bookmark to have a "join as player" bookmark to the game. =D