What program was used to create the .dxf files in thingiverse? I am having problems viewing them. I have tried a .dxf to .pdf converter and a couple of other programs. The most "success" that I have had was to be able to see some text and a couple of lines.
Inkscape has some support for DXF viewing though I have had some problems on certain files. Also QCAD which offers some kind of hobbled version can do it.