http://thebeachcats.com/pictures/?g2_itemId=11313
As Ron said, I'd chime in.
The pictured is Dave Tilley's tilting trailer design. It's very clever. The rack is winched over and you tie the boat to the beams. Read this to mean: NO TRAILER CRUSH. Then the boat is winched up and over and away you go. The mast goes over the boat. See picture below, yellow boat in bgrd has mast aboard trailer
The wheelbase has been widened to max legal IIRC 8'6" Like the catamaran, the wheelbase ensures stability and the way the rack carries the boat is low'ish to the road.
The rig is stable. I've carried my Square for prolly thousands of miles b/forth between Houston and Ocean Springs and the only thing it's done is one day in a 30kt crosswind the trailer fishtailed but it has never EVER lifted. Ever since, if I think the wind will be high I'll strip my trampoline back (I have a Perkins style tramp on my Sq).
The rack is bolted to a stock multihull trailer frame and its axle was widened. Simple to fabricate.