I didn't link to that slide out van Dyna, but I remember it.
When I say modular I am thinking about the various purpose aspects being removable, such as cooking centre, workbench/tools unit, entertainment/IT/music/film&photography unit, stripper pole.
The van is a factory built minibus, so it has full tracking back to front for all the seats (originally 16), and that means a lot of flexibility for moving units around, and the tail lift means taking them off is peasy.
First thing on the design front is a combined cooking/sink unit with fold out work area. Steel framed and finished in treadplate with large wheels, built in gas tank and lighting/water tank with electric pump.