Well as always this was instructional. The original bb file was done in Illustrator apparently at 96 dpi (which is the css standard). Editing it with Inkscape works fine until you save it, when Inkscape sets it to 96 dpi (like the input) rather than 90dpi as it used to. When the result is loaded in to Fritzing, the bb scale is too large (as Fritz assumes 90 dpi but the file is 96 I think). I've spent most of the day to figure out how to recover this, and I'll add that to the Inkscape tips thread in a bit. Now as to this part. It is really broken. It has busses (none of which are present on the part, but then perhaps neither are the connectors it references ...), pads that appear to have been freehand drawn in bb, very odd pin numbers internally a poor and incomplete schematic (which I tossed and did over entirely, with schematic matching the layout of the device pins in BB as is best) and no pcb svg (the original problem). So I created the pcb svg from scratch and fixed up the BB svg with new round all identical pads. I think this part should be correct, but as I don't have one to check, as always before cutting a PCB print out the footprint and check it against a real part to verify it is correct. If I can figure out how to contact them, I'll offer this as a replacement for their current part ... If the OP downloads this part it will hopefully do what he wants.
edit: Replace this file with one where the svgs have been post processed to remove the Inkscape badnesses (such as px in font size) which I forgot to do in the first one):
Arduino MKR Fox 1200_fixed.fzpz (36.0 KB)