Custom post-type and front-end-menu

Hi!

NOTE: This is a frontend-question. I do manage to create backend-menues as i want to. This question are about front-end structure regarding custom-post types and wordpress front-end menues.

It might be so that i haven’t clearly understood how custom-post-types and menues are supposed to work, have that in mind answering my question. I have made some custom post types wich should be shown of the front-end of the site (so far so good).

I managed to make the slug of this custom post type to dynamicly change depending on which page that are using a specific template. The result of this is that i can have a custom structure as follows:

http://example.com/about-us/offices/city/la/

Nice huh?! Works really well to hack around with some simple css on smaller single-menue sites (to mark active pages in the menue).

The big issue reveals when i tries to accomplish this on a much bigger site, especially when talking about the submenu. Due to the fact that the custom post type dosen’t exist in the menu, there are no parent to get when showing the custom post type.

I have written multiple plugins, but still I can’t seem to resolve this issue. I have tried solutions as rewriterule, endpoints and are sniffing on custom walkers (might this be a solution?). But I always end up in feeling that i’m too close to hacking core-functionality.

I have the feeling that there is a way to do this, but how? Appreciates all kind of thoughts and solutions.

Best regards
Sebastian