Since it sounds like you are using a servo, I moved your thread to the "Servo controllers and servos" subforum.
Can you elaborate what you mean by your "motor's power is not enough"? Are you referring to the video you sent us via email, showing the jittery movements of both your servos? If so, it does look like a power issue. (It might be helpful to others, who are following this discussion, to post the video in this thread.)
Can you post pictures of your setup clearly showing all your connections (e.g. connections between your power supply, Maestro, and servo)? Do you get the same behavior if only one of your servos is connected to the Maestro? If you have a different servo, that you know works, can you try connecting it to your Maestro, disconnecting all your other servos, and moving the servo with the Maestro Control Center to see if you get the same behavior?