Actually, now that I look at this, I'm a bit curious as to how the z-axis is strung up. Also, the z-resolution on this changes with height, a problem I think they ran into developing the Mondrian printer. I can't be sure, (I don't read French terribly well) but one iteration had a similar scissor lift mechanism for the z-motion, but then they went away from it, making me think that they probably didn't solve that inconsistancy.
While I'll remain sceptical on putting this in a backpack, I can absolutely see this form factor being desirable for use on a road trip in a camper van or on an RV where space is very limited for long periods, but can be expanded for a night or so. My parents are spending their retirement in an RV going cross country, and they often lament having to pay exorbitant amounts of money and sit waiting at one site for replacement parts when there is something broken that they can't bootstrap together a fix.