Looking at the rendered Ex40.

If we imagine the beam is 20'. Then splitting the beam in half is 10', which is pretty much the limit of the trailerable ww cabin width. My guess is the 10' split line is at the lee edge of the ww outside cabin seats.

So, probably the 12' trailerable could just reuse the Ex40 cabin.

The problem is the bridge deck. Or, more specifically, the helm station, winch's, and toybox.

The walkthrough rendering of the Ex40 seems to have forgotten the toybox/anchor system. To my eyes it looks hollow under the winches. Rob has said Steinar is trying to heat his shed to get some infusions done. I guess that is a race against the season, as he is north of the Arctic circle, I think. So, he's busy for a few more weeks, and our good thoughts go out to him. He is, after all, doing a most sacred thing, building a boat.

That said, does the toy box/anchor high enough stressed to need to be solid between the beams? Or can it drop in or flip down?

Or does it need to be solid to the lee beams and it needs to be part of the lee cabin ~12'?

If the spacing is tight, perhaps do like the C60, no cabin attached seating, and the box is the seating?
http://harryproa.com/wp-content/uploads/2017/12/C60-006.jpg