Problems exporting to .dxf

I am using Inkscape 0.48.5 r10040 on Windows 7 to create intricate mechanical parts for contraptions that I am cutting via laser and water jet.

Previously, the laser cutter software could import .svg files and I had no problems, but the machine's control card failed and was replaced with a more sophisticated card which required new software. The new application, RDCAM, does not import .svg files but will import .dxf files.

When I save Inkscape .svg files as .dxf files many problems occur:
--Objects are broken apart at vertices
--Additional lines may be added between arbitrary vertices of the broken objects
--Curves are lost or changed (even circles are no longer circular - they have a point at one of the vertices)
--Sometimes separate objects are connected
--Scale and stroke width are lost

The issues occur even when opening the .dxf files again in Inkscape. I previously reported this and was notified that it is a duplicate of bug 1429184 but am not sure if it has been addressed. If I use a friends Adobe Illustrator to convert .svg files to .dxf then the problems do not occur, so the issue is definitely in the converting process within Inkscape.

I hardly ever update software as I'm paranoid that updates may affect usability of already created files, but please advise as to whether updating to the current version of Inkscape will fix this issue or whether there is another way around the problem. I love Inkscape and would like to donate $ to further development, but am currently unable to utilize the drawings that I've created and am unable to use it to create drawings for future projects at this point.
Thanks,
Brett