We are experiencing an issue where tickets at a certain point in their workflow cannot be advanced, because no workflow action buttons appear. I have checked the Conditions for one of the actions that should be possible (Because I thought I'd start with getting -one- button to appear) and the only condition set is a single "Only users in project role" restriction. I checked that project role, and the correct people are in it, but still can't see the button. I also tried setting the "Role" in the restriction to "Users" (which contains essentially everyone) but still the button does not appear.
Where else can I look for potential reasons for a workflow transition button not appearing?