Well you may be finding a couple of problems with the way it counts extension mobility users as separate users rather than combining them with the Enhanced user licenses, the other problem is that if you haven't associated a users multiple devices to the single user then this shows as several user licenses rather than just a single user with multiple devices. Because of this you look a a site with CUWL you'll often see it says you need many more users than you have but of a lower license type.
Other problems include the way it counts public space phones and the way it adds up unused DLU's in CUWL since it expects to see the full number of DLUs but in the last year or so Cisco have issued a reduced number of DLU's as default so you dont have enough DLU's to make up full CUWL licenses.
Oh and to finish it all of Cisco have now totally changed the licensing so the UCT is little more than useless until these issues are fixed and it is updated for the new (September version) of 9.0 licensing. I have given up with it until there is a new 9.1 version.