Danilo,
Configure the printer as you would any other except in windows use generic/text only as the driver, and don't give it a PxPlus driver. In *nix you can also specify no print driver. Simply open a channel to the device and print your ZPL or EPL commands. I have done this literally hundreds of times with different customers. The biggest mistake is usually to try and use the printer's own driver.
Hope this helps!
Michael