Comment 4 for bug 600472

sounds similar to Bug 585021.
could you try this procedure:
- Edit->Select All
and then use :
- Path->Object to Path
- then, with all objects selected, force a bit of a translation by selecting the entire group and hitting the up arrow once and then hit the down arrow once to return to the original position. If all goes well this should remove the transform elements from the diagram.

When I use this method I get the attached .dxf file which I think contains all the required elements.