Oren, thanks for jogging my memory re the Lomo Belair. It is a strut type folder. I believe that lenses better than the original issue ones have been adapted to them.
I went to 6x12 with a 4x5 monorail view camera, didn't use a 4x5 Crown Graphic because the shortest lens I wanted to use won't work on one.
I have no experience with adapting the Lomo to take other lenses or with adapting a Folding Pocket Kodak of the right size either. That said, if I had to do an adaptation I'd start with an FPK because the camera's front standard rides on rails on a bed, just like a Graphic's. This means that if focusing on the ground glass is arranged -- some models of FPK allow this, but only before film is loaded -- any lens that will work on the camera at all can be used. And of course one can use the GG to make a focusing scale ... This is much harder to do with a strut camera like the Lomo.