How to allow registration with or without blog.

Site is Multi-site, Sub-domain, BuddyPress, BBpress, Pro-Sites, Anti-Splog. I believe this is all that is needed for this problem.

I deativated both Anti-splog and Pro-sites so they aren't he problem.

I have Anti-Splog set to allow two blogs a day and it works when setting allow registration and blog.

There are 4 option to choose from Network Admin->Setting->Network Settings. They are:

1. Registration is disabled. Works as it says.

2. User accounts may be registered. When selected my users can't create a blog after registration and login into the site. I've looked every where.

3. Logged in users may register new sites. When selected no one new can register.

4. Both sites and user accounts can be registered. When selected they must create a blog when registering instead of optional.

Some of my friends have told me they don't want to create a blog but want to register to become active in groups and forums.

How do you allow registration with or without option ?

I know I can add instructions to create the blog and make it private but it's not real professional.

Any thoughts or solutions?