EDITED :

I managed to resolve my problem with help of the french community...
Sorry to have bothered...


Tdldp

PS : There really should be something done on the personnalisation of that register.php for further versions... I imagine how hard it must be for a complete novice who wishes to personnalise those forms, where to start from, where to go ... I have read that it is being implemented to version 2.6 but it won't be a luxury...