Is there a way to call members and groups to all subdomains on a child theme?

I am running the magazine as exactly that, a magazine

So I have writers and they are given their OWN blog as part of the community and they contribute to the original main site blog by using that blog permissioned in the drop down list of “their blogs”

This is my question:

When I allow the blog and set up the theme get it all together for them.. when its published..

I would like for it to have the same members and groups so its a seamless experience from the front of the site, and people can actually navigate around this small world of blogs that are all attached to one main “frontpage” magazine. I would also like for these writers to have their articles appear on their subblog , (and on the front page ) of the main magazine (if specified) by writer or contributor.

This is more like a community “magazine” to me , and its ultimately what I thought could be done, however no matter what I try , this is not happening for me.

Also, when a user uses the dropdown menus if there are too many categories (sometimes as few as 2) the user is not allowed to click anything that is in the same space as the front page banner. is there a fix for this?