We have an environment - frontend with AD account and backend with Custom User List.
The problem comes when a user needs to borrow a license from the server for development purposes (or to open a file created by another user) , by doing File-> Open In server. The only way this seems to work is when we use the NT Identity, which then assigns another license to that user based on the domain. So 1 user can consume 2 licenses.
Open In Server - I have tried to login as a user from Custom List and got an error message:
Connected to the server OK, Negotiations Timed Out
Switching to HTTP tunneling
Connected to server OK, Security settings denies access