Thanks for the quick reply!
Well, the software updated (without asking me) when I opened it up before I began having all this trouble.
I tried uninstalling and installing the v29 software linked to through the XYZ open mod topic. I also tried the XYZ open mod .exe replacement (which is actually what I had been using earlier when it worked). Nothing works.
Now I went in and re-installed the latest XYZware (v34.7). Still not working.
Tried re-exporting the DWG from Illustrator in mm, and working in Creo Direct in mm - had a strange scaling issue, but extruded, etc and exported from Creo in mm. Imported into XYZ just fine, but still slicing off the top 'layer' (1.8mm). You can see what looks like traces of the details in places, like someone started to draw them on the base 'block'. Have also tried printing to see if just displaying wrong ... prints exactly like it looks.
BTW, I have tried this on normal, good, and excellent ... and changing the settings manually to .1mm layer height. No success.
Have though about jailbreaking the printer and putting Repetier on it, but hesitant to bite the bullet 'til it's out of warranty in June.