At default all veritas panels have the engineer and master user.
Master User can add extra Users (R8+/Excel/Digitas only)
Engineer can add extra engineers (R8+/Excel/Digitas only)
You can't do Engineers from Master user and User codes from engineers.
You can lock the Engineers Code only on the Veritas and nothing else.
The panels that are not 00 you are able to determine the soure of the tampers in the User and Engineer modes, via event log or the test menus on the Prog version of the panels some allowed engineer only to id the tamper and others allowed the master user.
Lets face it theres only a few places the tamper can be coming from, and go through the basics and isolate possible sources if you cant access the diagnostics on the panel itself.
All this is very well documented in the Master user and Engineers manuals.