Buddypress and Membership plugin

Hi,

Following on from my previous topic - https://premium.wpmudev.org/forums/topic/multi-site-1?replies=13#post-173187

I thought I should start a new thread here, as my post is now related to the Members Plugin.

To recap:
I have lots of offices - and I'd like to connect the staff in those offices through a buddy press site.
When a member of staff signs up, I would like to automatically assign them to a group for their office, and grant them access to view news from their office.

So an example of the idea would be: when a Member from Office A clicks on "news link" they should see the news for Office A nb: http://example.com/archives/category/officea

When a member from Office B clicks on the "news link" they should see the new for Office B... nb: http://example.com/archives/category/officea

I've been told it's not possible to automatically grant access to groups via the members plugin (I'm quite prepared to pay for this feature - like I said... I'm desperate) - but I can do this manually when someone signs up.

Staff should then be able to create their own groups, search for members (from all the offices) and friend them etc - all standard buddypress stuff.

So to set the news category stuff up, I've used the membership plugin. I've set up a level for each office, and assigned the relevant news category as a positive rule and then applied that level to the members of that office.

However, it doesn't work. When logged in as a member, I see all the news... not just the category for my office.

So I did it the other way - and set up a negative rule, selecting all the categories that I don't want the user to see... but this didn't work either. I can still see all the news, not just the news for my office.

Does anyone have any advice on how I can achieve this? I'm becoming really, really desperate now... I've got a lot riding on this...

If anyone can help, I'll be eternally grateful - and promise to send you beer.

Thanks,
Rob