James,

First a comment: I see you mentioned "Firewall mode". The mode has nothing to do with user license.

Once Xeams determines more than 5 users it will automatically disable "Filtering" under Filter Management/Score Configuration. If the user count goes below 6, check the box again to enable filtering.

Answering your specific questions:

a) Enable filtering under Filter Management/Score Configuration. That should stick now as long as the user count is 5 or below.

b) No. This is not a permanent config

c) No restart is required