did you select the select chain in the offset entities properties? you don't have to select each one, if you want to offset the whole chain, you can do as I show.
How are you selecting the edges to be offset?
Is the inner white area a face or a hole?
I figured it out... funky model from a vendor.
The corner's are made up from a bazillion nasty splines the guy did. The other corners are made up of arc's in his original solid - they offset normally.
Seems that when they translate out from Pro-E or whatever to STEP/IGES/ACIS they sometime's have issues.
It's a view of an edge feature - the white is open. Me no use the fancy pants backgrounds. I'm an old SW user from 1996. I like the good 'ol white.
I'm not one for modeling on a conference table backdrop...