The creator of the game must make sure that that particular game takes up an available slot on the list. Depending on their level of subscription, there are limits to the number of players and the number of games that can be shared. It is possible you may be running up against that: From the Help Center : Free Users may purchase any compendium. They may only share their purchased compendiums with one active game that contains no more than themselves plus 5 players (6 total). Plus Subscribers may purchase any compendium. They may share their purchased compendiums with three active games that contain no more than themselves plus 10 players each (11 total per game). Pro Subscribers may purchase any compendium. They may share their purchased compendiums with five active games that contain no more than themselves plus 15 players each (16 total per game). Free Plus Pro Compendium Sharing (no. of games / no. of players per game) 1/5 3/10 5/15
