Thanks for the pointer, I'll have to give it a try. I've been looking at various M-CAD tools over the past few months (in my spare time) trying to find something sufficient for my "occasional" needs for 3D modeling and package layouts and such. Solidworks appears to be one of the best, but as with most high-end tools they aren't cheap.
For update - I opened a support case with my Cadence reseller on this issue and got good fast response. They quickly duplicated my problem and got the same "import" response on the last three versions of the tool at their end. Conclusion - there must be "something" in your dxf that's confusing the Cadence importer - REALLY? (I thought that's why I opened the case). Guess the good news - there wasn't something that I was doing wrong to goof things up.
Our joint conclusion was I would be best off to look at the dxf, get the coodinates/measurements of stuff I needed then manually re-create the features in PCB editor. In this particular case, I only have 20-30 things to create as opposed to 1000's. <grin>
Oh BTW - I reran my DWG-DXF converter to create the dxf in two other newer "formats" for AutoCAD 12 and 14. No improvement, the import to Cadence did the same screwy stuff. The dxf2a log files just reports a few "illegal characters" being replaced for whatever reason. Curiously though when I try to use the "view selected layers" button on the importer, it does error out, with several reports of
(SPMHDB-70): Buffer contains overlapping segments. ERROR: Failed to add (LW)POLYLINE.
I haven't found documentation of this error code yet. It may be a clue, but I best be getting on with the job at hand.