Finally got to CUPS web interface, added new printer there. Saved changes, and clicked on "Print test page"--this is all from VL-5.8 Standard laptop wirelessly connected on home network, to HP Officejet j3600 all-in-one printer on a Windows XP MCE desktop also wirelessly connected downstairs on home network. So, 35 minutes later, I go to check the test page on that Windows computer downstairs.
Nothing printed, but in the print-job list (on that Windows computer), there's my document, called "Remote downlevel document" by user "Guest". I'm not sure if "Guest" should be there, since I explicitly used a username and password in CUPS that is legitimately on both networked computers.