Hello, ve run into this problem actually about year ago.
the problem i don't have a printer at hand so i have to export my drawings...(maybe it would work if i had one or if found some linux printer around)
I am using Q-cad on 32-bit Fedora 11 linux system.
when I want it to simply to export drawings into pdf or ps it seems ok. however windows' adobe does not open pdf files
at least here in linux Evince shows me both pdf and ps exports full size, still if i for example try to export it with evince printing frame gets messed and croped same as with ps2pdf.com converter!
so the reason hides somewhere in the programm.. i think i will try windows version of it. maybe also vec2web for image conversion