I've replied several times on the DXF / DWG thread, and many other feature request threads (and I would prefer that this particular thread doesn't turn into a duplicate of a particular feature request), but...  When we released Designer originally (5.5 years ago) it was marketed as "Vector illustration and design". At no point did we mention CAD, or technical illustrations. A lot of the complaints that we receive with regards to this seem to be along the lines of "I've just switched from pr