I have my custom Screen operational for my custom Issue Type in a specific Project (create/edit/view), but when I open a related Issue (that has been already created) there are some extra fields. These extra fields are not present when creating an Issue (uses the same Screen).
The fields specifically that I see when editing/viewing the custom Issue Type are: Assignee, Reporter, Releases, and then further down in the 'More fields' I've got: Original estimate, and Time tracking.
I am Project Admin. The extra fields are not part of the custom Screen, but in the Screen settings it says 'We've only displayed fields that you have permission to edit and aren't hidden.' Not sure if that is relevant.