(The Dell A720 is a rebranded Lexmark that also uses the z600 driver).
It seems that you DO need to change permissions on various files and directories for the z600 driver to make it compatible with CUPS 1.1.23, as provided in pakt's .pup (if you don't, the z600 driver won't work) - see the following link .....
Just got back from a friends house trying to make his Lexmark Z730 work with Cups & 215. I failed but saw your post, unfortunately the link brings up a no such post message. Could you share the message or find a link that will work? Many thanks,
His computers make 3 converts so far for me. The others had HP printers and it was a piece of cake.
Thanks for the quick response, I have read the threads and will let you know how it turns out. Will be at least a week before I'm able to visit the person with the printer, don't really see him doing it himself.