Make 2D failing with hugh files in Rhino 6

I experienced problems with the make2d command in rhino 6. The command only works fine when also drawing hidden lines. Make2d then exports all the lines on the hidden lines layer which makes it more or less unusable for later processing in illustrator or so. Is it a mistake of myself and how i set up the rhino file or is it a common bug?

When trying the same operation in Rhino 5 very thing works perfect except from the problem of not being able to group the lines of every single object.

Best,

Max

(I tried to attach the file to this post but the upload canceled itself all the time)

Hello - please send the file to tech@mcneel.com. Please include a link to this topic in your comments.
If the file is very large, please SaveSmall, Zip the results and upload via www.rhino3d.com/upload, to my attention.

-Pascal