I can't help you with the Casita
forum, but here is a direct link to the 2016 Rally Map
. Clicking on any of the trailer icons will bring up rally
information in the left sidebar. It includes brand-specific rallies (which typically welcome owners of other brands) as well as general egg rallies, so it seems to be fairly comprehensive. Hidalga, the map coordinator, tries to make it so, anyway!
Rallies are indeed one of the best ways to get a look at a variety of different molded fiberglass trailers and talk to owners. If you contact the event coordinators they can advise you about scheduling a visit and perhaps give you an idea about what kinds of trailers are expected to attend. I hope I understood your question correctly.