I've seen this warning on the Ultimaker 2 before. It just pops up on the LCD screen, and I hit "Continue" to proceed through the warnings and then the print starts. Prints great. The Ulticode is just a Cura-specific thing, but it's not needed to print on the machine.
They already have the DreamMaker Pro settings in the Configuration Assistant. Just load that profile. It will automatically use the correct firmware, since the profile controls the firmware settings as well (watch this if you want to learn more about that: https://www.youtube.com/watch?v=NYPUAqT4UyI)