INNOVUS - write_lef_abstract -design_boundary Option

Hello,

I am seeing:
"**ERROR: (IMPLF-1000): Illegal value found for -design_boundary option."
when trying to use the -design_boundary flag with write_lef_abstract. The man page simply says to use a point list, which I have tried different methods of creating listed below:
as a string ("x0 y0 x1 y1")
as a string in a list ("{x0 y0 x1 y1}")
as the [dbGet top.fplan.boxes] returns ("{{x0 y0 x1 y1}}")
as a polygon-esque list of points ("{{x0 y0} {x0 y1} {x1 y1} {x1 y0}}")
And none of these have worked for me. Can someone please give me insight as to what a point list should look like?