The Z key is used to temporarily zoom into a part of the drawing. This…
Vectorworks Tip #058 – DXF Viewer
When you export DXF/DWG files, you should check to see what you had exported from Vectorworks. What you need is a DXF/DWG file viewer. DraftSight is a free viewer that lets professional CAD users, students and educators create, edit and view DWG files. DraftSight runs on Windows, Mac and Linux. You might want to try this getting started guide as well.
http://www.solidworks.com/sw/products/draftsight-getting-started-guide.htm