arduino and 3in1 controller unit from lamav3 heli

Hello, Im trying to control the motors of my indoor lama v3 helicopter though its 3in1 control unit with my arduino. This one has 2 servo cables, one for the throttle and one for the rudder. Im guessing that i must feed the signal cable with the same way as a servo, so im using the servo library, but the results are not good. I cant have good control of the motors. They are running for some time and then stops. Does anyone have any experience on this one?

Ok i managed to fixed that problem. I have some other questions now. 1st for the yaw. If for example the imu heading to one direction(i.e at north) when it starts, i get from the euler angle a ~0 . If i turn it left or right at leave it there for some seconds and then turn it again to its starting position the reading now its not ~0 but ± value. Can anybody explain me why is that?

2nd. If i pitch down or up the imu and hold it there(without turning the board in a way that should affect roll) , the roll value changes for some seconds and then returns slowly to 0. Why is that? My thought is that is caused by a filter… If anybody can help i would appreciate it.