Using Without Registration

I was wondering if anybody has used WP-Members without the registration process. In my situation with a relative small (60) members for a pubic service members.
I am in the process of converting a mysql database into WP-Members. All add and delete functions are done by admin. Members will be able to update a small subset of fields and display information on other members.
I am using WP Ultimate CSV Importer for data transfer (about 160 rows because we want to keep historical information on past members)

I do have a career in programming but not in php, but starting to figure it out.

I simply want to ask has anybody done this or operate this way without the registration process for anything I need to beware of or any “gotcha” things? I would really appreciate any pointers or tips I might miss. Thank you!