Thank you to Frédéric Large,
Here is the Information I got from him :
LK_USER_REGION is an historic table that were used to manage the Sales Region for 1 company (Sales sectors : NORTH, SOUTH, etc...) where a Sales guy (Efficy User) is attached to this Region, that is why we have a standard field REGION in the
All of this is used to facilate to do Sales Reporting.
This mechanism is used on some Efficy France Customer where "France" (the country) is divided is 4 big regions, all of them divided in 12 sectors which are attached to 1 sales guy.
In order to use this functionnality, we only need to modifiy the User page in Condify in order to make it "typeable".
So this is a Conficy Custom, the page is called "UserEditForm.htm"
And you just have to add the code to edit the field in the right place in the file: