This is a continuation of the saga I've posted about before.
Recap: I had moved my Epson R1800 printer to Firewire to free up the USB port. But then I found out Parallels doesn't virtualize Firewire.
So I moved the printer back to USB. Things seem ok. Some time later I go to print from Lightroom and I find that I'm back to the CUPS+Gutenprint printer driver which doesn't support all the printer features. I'm not sure how that happened since before the USB->Firewire switch it was using the Epson driver.
More time passes and I go to print from Windows under Parallels. The print job goes into the queue and gets stuck. I can't even delete the print job or the printer. I try disconnecting and reconnecting the USB port to the Parallels VM. I try rebooting Windows. I try rebooting the Mac. At some point during this thrashing my print job comes out and the printer deletes. I recreate the printer, thinking that it's now going to work, but my test gets stuck in the queue as before. I thrash some more, but can't seem to hit on whatever combination it was that released that first print job.
I search on the web and find various discussions of various problems more or less related to mine. One person says it takes 5 minutes for his print jobs to emerge. Maybe this was what happened with me - not anything I did while thrashing, just the amount of time I thrashed. It seems bizarre that it would take 5 minutes. What is it doing all that time? And why does it work after whatever it is doing?
I had gotten an error message about the Epson Status Monitor 3 (why 3?) and some of the discussions mentioned this. I tried disabling it and killing it etc. but it didn't seem to make much difference.
The strange thing is that I could swear I had the printer working from Windows via USB before I switched to Firewire. So why doesn't it work now? Changes to Parallels? Who knows.
Eventually I found Finally got Epson Photo R800 printer working in XP VM on the Parallels forums. (an R800 is the narrow carriage version of my R1800) It gave instructions on how to share the printer from OS X and then access it using Bonjour on Windows. I had run across references to this before but they all talked about using a generic postscript driver on Windows which is not what I wanted. I needed to use the Epson driver to access the printers features. But these instructions used the Epson driver.
The instructions were for the printer connected by USB but they mentioned they would likely work with Firewire. Since that's what I really wanted I thought I'd try it. Nope, couldn't get it to work. (no URI for Firewire device?) Back to USB. This time it worked.
The only place where I had problems with the instructions was with choosing the printer type. Bonjour only showed the generic postscript option. I had to choose Have Disk and then find and select my Epson driver.
Several hours later, I think I have the correct, functioning printer setup in both OS X and Windows. And even better, I think I should now be able to use the same method to access the printer from other networked Windows machines.
A few days ago someone suggested buying a MacBook for someone else. I said it probably wasn't a good idea because they'd want to run Windows programs. They said "I thought you could do that now?". Yeah, well, you can, but ... it can get ugly.