Some of the comments above on founding a religious order are correct, and some of them incorrect. Those who wish to found an order are highly advised to speak to a canonist on the subject. I myself am specializing in consecrated life (and association of the faithful) law because of my personal interest, but any canonist knows the basics of establishing a religious community. A person does not have to be a priest or nun to found an order. [My disclaimer is that I will not be a canon lawyer until later next month.]
You asked about the SoL’s disclaimer… A “new” form of consecrated life must be submitted to the bishop (who in turn gives it to Rome) for approval if there is ever to be canonical recognition of the life. It is in the best interest for a prospective candidate to see whether such a community is actually pursuing such recognition or is just waiting for a miracle to occur with Rome all of a sudden discovering its existence.
The truth is, members of groups without canonical status or approval are especially vulnerable when it comes to questions concerning their rights. Religious have rights by law which are not necessarily extended to privately consecrated individuals consorting in community. I have to say from my experience with religious orders and wanna be orders that there are enough problems in religious life with established constitutions and rules. Trust me, there are scads of problems in established communities that non-religious have no idea about. It’s a zillion times worse with emerging communities.
I am friends with a person who just obtained approval for her community’s new form of consecrated life. She had the able assistance of one of the best canonists in America and I was glad to see her community get that approval.
With respect to private associations of the faithful, there is no restriction on their expanding into other dioceses. With respect to the use or non use of habits, it is best to defer to the local ordinary’s judgment. The habit is a public sign and he may restrict its usage to those of diocesan right if he chooses.