Hi, which driver did you use? If you use the google search you could find some help. like:
..."I've a ML-1750 and since I have no adequate Samsung driver I'm using a HP laserjet 4 driver with CUPS Gutenprint V5. Works perfectly."...
If there is a rpm package for your printer you could use alien to install it
Maybe there is a problem with your share. In my network I use the guest account in Windows for the shares (I know it is not save, but it's working). So the login is guest with no password.
As address of my printer I use the IP address. Be shure to run the dialog as "root". sudo gnome-cups-manager
I hope this will help you