I apologize if this is either old news to you all or not directly relevant, but FWIW SRI had some "web" type CLIM backend:
http://www.ai.sri.com/~pkarp/clim-www/tool.html
The source code is available via a URL on that page. I made some half-hearted attempts to build it under SBCL+McCLIM, but did not get too far.
It definitely fell into the "yak-shaving" category for me, but it might have some relevance for you guys (if I understand correctly what you are attempting).
-jm