Had a flight take a 7 Hour MX delay MXP-EWR. Plane was a 762, subbed for a 752, which took an extra fuel stop in Gander. "We have a gain reviewed your request for cash compensation and found that we complied with all the applicable regulations at the time of your flight. I understand that the delay was, at best, very frustrating and truly regret you were disappointed. Please let me explain why cash compensation is not applicable under European Regulation EC261. Because all routine preventative maintenance actions were performed on the aircraft as scheduled, and the extended delay could not have been reasonably predicted or avoided, the event is considered force majeure and exclusionary to the mandatory compensation rules. Please know that our legal department carefully reviews each of these matters with our system and techincal operation groups to ensure we are in full compliance with the appropriate legal standards. Although the cause of the irregularity was extraordinary and unable to be avoided, we did what we could to minimize it, and hae nothing furthre to advise at this point. Because we do recognize that your flight plans were negatively impacted, as a tangible gesture of our regret, we sent you an electronic travel certificate valid toward a discount on a future United flight." (No compensation was enclosed, nor was it e-mailed) What do I do now? Do I continue to beat this dead horse, or file something with European authorities.