It was the receiver!!
I am happy to inform that the culprit was the receiver. I swapped the optima 6 for an optima 7 and voliá!! It worked perfectly with the flash 7 on normal, with two ailerons and rudder nirmal, ailerons on channel ail 1and 5 ail2.
now a question... should I ditch the optima 6 or send it for repair?
Regards,
Patrick