I appreciate the fast reply.
I found some stuff on nginx and wordpress multisites. Just strange, when I disable O.S. the posts are fine, or if they are not part of a series then they are fine, as soon as I add them to a series they go into an endless redirect that never resolves.
In any case, nginx is above my head, I'll have to have someone else in the company take a look at it I guess, for now I'll roll back to the previous version as it was stable for me.
Really appreciate your help man.
If this is the kind of free support you provide, then I'm likely to sign up for more in depth stuff, and, if you can even give advice on nginx, I'll be signed up in a sec as I'll have to wait until Monday (when the site needs to be ready) for our nginx guy to take a look, as he is out of town.
In any case, I'm seeing some awesome possiblities for the OS series pluging for our customers and I hope to get this issue resolved so we can continue our relationship ;) Thankfully we have a dev and prod server so we can test new versions on dev before upgrading on prod.
Take 'er easy.