How to associate automatically groups with group type ?

Hello, thanks for your work ! But I think only admin can associate groups with group type.
I’ve 3 member_types, 3 user role. Each user_role is automatically associates witha member_type.
Thanks your plugin I created 2 group types.
I wish to associate groups created by member_types (or user role) 1 & 2 to group_type 1, and groups created by member_type or user role 3 to group_type 2.
Could you say me how to do ?

And how to don’t allow members of group_type 1 to see groups of group_type 2 in the groups list.

Thanks a lot