Use CB Auto Action Plugin to create "sub users"

Hi,
Is it possible to use the CB Auto Action plugin and/or a trigger to create a sub-user or "secondary" type user based on a field during registration?

Here is the scenario:
We are using CBSubs to sell membership levels. Some of our membership levels are Family memberships. The main member specifies the other family members' names during registration. We would like to create separate accounts for those family members automatically so each family member is able to participate in the community. They would need to have the same group as the main member registered them for to allow the proper access on our website.

I thought I had read something about CB Triggers being able to do such a thing a while back?

Yes, you could use a Code action with PHP method and using the below CB API create a user after the registration trigger.

www.allmysocials.com/directory/tutorials/item/237-create-users-through-api

Thanks! I think that will work! Another question, using CB subs I'm assigning users to a user group based on the plan chosen. I need these sub-users added to the same group as the main member. Will I be able to grab the needed variable when the auto action runs? Is it posted with the registration form data like a hidden form field or is there a script that runs after the registration process?

You're wanting to check that they've selected a certain field at registration? Don't understand what you're asking, please be more specific. If you're wanting to check that they have another usergroup you can use the [gids] substitution with a Contains operator then supply the usergroup ID you're trying to match.