It appears that I am having similar problems...
First, a quick environment run down - my situation seems a little more kludgy because I don't use PS enabled printing devices, but RIP software instead:
From a B&W G3 ( one w/ 9.2.2 and one w/ 9.0.1?)9.2.2 w/ carbon lib 1.59.0.1? not sure of carbon lib version
ethernet to HP JetDirect 300(something) connected to HP DesignJet 330 (infoware is now strydent - powerplot 2.0.2 - no plans for updating software)
ethernet to AXIS 5400 print server connected to a Lanier 5025MFD (11x17 capable)(strydent powerprint pro v4.0)
after upgrading to v9.5.1 I noticed the following:Save a drawing configured for D-size printing on the old 330. Go to the chooser and select the Lanier (which is really a Ricoh Aficio 250). Open up the drawing and change the page setup to a tabloid size, landscape. It doesnt seem to matter whether you save the drawing and exit or print immediately - you are always presented with a PageSetup dialog which does not show the changes you may have made previously. Insted it seems to default to either letter size, portrait OR it will remain on tabloid but with portrait instead of landscape. ADDITIONALLY, some of the Lanier's printer options, which were available before v9.5.1 (like paper tray, gray scale density, etc..) are no longer available.
Now, the fun part!! Change to the plotter in the chooser and change page setup back to D-size and the very next time you try to plot - BINGO!! you get the page setup dialog. Setting up the page size and orientation in the page setup dialog box and clicking OK will bring up the Print dialog window. Again, not all of the options are available that were there pre-v9.5.1 (i.e. 9.0 or 8.5.2?). Then hit Print... It resets to some letter size default and page orientation and the plot comes out, well, FUBAR!
So, now take 8.5.2 - open it up and presto! Everything is as it should be.
NOTE: To all responding with Distiller comments! I didn't mention it because we don't use it. This is going through driver software that worked prior to v9.5.1.
This is neither a "base" operating system problem, nor a printer driver problem. At least in the sense that printing that is NOT intercepted by Carbon Lib functions works just fine (oh, and yeah, I tried disabling Carbon Lib in the extensions and the results were the same). This is looking very much like a VectorWorks printing problem.
Several hours of running through the differenct permutations has left me a tad bit disappointed. Please, don't ask me to check whether or not all the cables are connected properly... If you've got hard core trouble shooting techniques I'd like to hear about 'em, but keep the clearing PRAM suggestions for those who don't know any better.