Purchase of PRO version

I would like to use s2member for an alumni website that I am creating. I have the FREE version on other sites before. However, I need the functionality of the PRO version for this site. In particular, I would like more information on the following:
a) I understand I can use LEVEL 0 for free registration. However, is there a way for an Admin to approve the registration. We want to check the users who register against an Alumni database. The client will do the check manually, but wants an approval flag/setting prior to giving the newly registered user access. They don’t want any paid subscriptions.

b) Registration form should also have customer fields that can be defined by client – like Date of Birth, year of Graduation, Maiden Last Name. How do I implement this?

b) Approved and registered Members should have the ability to see the list of other members/alumni. The search should be on custom declared fields in (b). Is this possible and can you provide me the link of how to implement it?

Thanks
Kevin

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