Do you have.... Demiplane Linked to your Roll20 account? Daggerheard (Supported By Demiplane) set as the Character Sheet on the Roll20 game? Asking so I can try to replicate the process and see if I can find anything out about this. If you do have both those as YES.... I would say close your game, Launch Game again, and try clicking 1 Adversary and wait up to 1-2 minutes. You might see something spinning on the character sheet saying something like "Updating character engine", and then it might load the Adversary after that. In my testing so far, on a new game, it loads the Adversary character sheet ok (after spinning and waiting to update the "engine").