Tried posting this in CMS5 but with no luck, so I'm trying here against my better judgment of double posting..

I need to write an entirely new EPiServerFriendlyUrlRewriteProvider because I want to be able to exclude pages from the path based on a property on the page. Certain pages in the tree are there only to structure data internally and shouldn't be exposed to the visitor in the url.

So what I'm wondering is what do I need to think of when doing this? I am familiar with writing my own provider and which methods to override but I'm sure there are a lot of things going on the the default provider that I'm not aware of.

Also what's the best way to build the path, traversing the pages using getpage and ParentLinkUrl?