on SW2013 I'm having a problem with imported DWGs that have contours in dashed lines:

I import a DWG/DXF as a new sketch.

I can't seem to select such contours as regions to extrude/cut (I think because technically they are not closed contours because of the gaps in the lines)

When I use the linestyle toolbar in sketch mode and change the linetypes of the dashed lines to continuous, it looks all fine in sketch mode.

But when I exit the sketch, they are still dashed and I can still not use them as contours to extrude/cut.

Is there a way to fix this? (and/or: why can't SW see that it's just a closed line anyways? Seems quite dodgy)