For assembly purposes in Solidworks I insert sketches of aluminum joinery profiles in dwg to extrude them on SLDW
Not rich alas I am working on version 11 of SLDW, for some time now it has been impossible for me to copy and paste sketches from autocad or drafsight in SLDW
It is true that the versions I work with (drafsight or Autocad LT) are very recent, does this explain that??? Or does it surprise you and you have a solution?
For example, I attach a DWG file, which I can't copy into a solidworks sketch. Grrrrrrrr
make sure CTRL-C on the profile and CTRL-V in a sketch??? If not, you can just make a clean DXF with the desired profile then file==>open and you select your DXF then you select an MEP and then Improter in a new room as: 2D Sketch then you click next; Select Millimeters in the units and choose the part layers you are interested in, then next and finish... At home the 2 ways work very well...
with SW2012, I tried to do Insert/dxf-dwg, it gives me a message "invalid or incomplete dxf/dwg file". It is likely that there is a generational conflict
In your case: - I will clean the DWG to keep only the essentials; - I'll save it in an old version of DWG (2010 is enough)