Thanks for your reply
, but I already did what you say.
The only options available in "Update server" are:
devpacks.org Community Devpaks
or
Dev-C++ primary devpacks server
and both need an internet connexion.
It's too bad that this plugin don't give the possibility to make it in an other way.
I found no option where you could, for exemple, select a folder in witch your downloaded your devpack and then install it, just like the devpacks manager in Dev-C++.
Thanks anyway