I set it up as a postscript printer. What I did was to just select the Lexmark C720 postscript driver when
setting up in ecomstation (gets you pscript.drv). That gives a nice icon and I renamed it C522. Its running as a network printer and gives beautiful output.
I did update the firmware as well. Couldn't get either the browser or tftp
to work from ecomstation, but could ftp the file to the printer and it
then updated.