Thank you for your post.
We have a Epson Stylus Photo 900, which may be related, and it prints fine on a Mac. However, we do have some problems on Windows, but only when printing to a file with that driver active.
Unfortunately, we do not have an Epson Stylus Photo 1900 here to test, so I cannot determine whether the problem lies within FileMaker, the Printer Driver, or the information from the printer being sent back to the application.
If you are able to narrow the possibilities, please let us know.