Perhaps I'm doing this wrong, but I can't change print settings from within an 
application, e.g. using Okular, FF, etc. I cannot change from colour to 
greyscale.

I can only change these settings if I login to http://localhost:631 and change 
the printer default settings there.

Is this how it is meant to work - what are plain users meant to do?

PS. This is a networked printer.
-- 
Regards,
Mick