Async Pluggable Protocol vs. WebRequest

I have an app that needs to work with its own uri scheme. Instead of http:,
I'm going to use wwkb:

I will register my uri prefix to run my app, and it only needs to be
available when my app is running.

Here's where it gets tricky. wwkb: will retrieve HTML from a database. I'm
going to have a web browser control in a window and I want to retrieve the
HTML from the database and then display it in the web browser. The links in
the HTML will be converted to wwkb: links instead of html links, so the web
browser needs to be able to accept that.

Will overriding WebRequest do this and if so, is there any sample code
anyone can recommend? The MSDN docs haven't been great on this.

I'd rather not go with the Async Pluggable Protocols architecture, if
possible since it looks like there are some issues implementing the COM
components properly in managed code.

Thanks.

Pete