Dave you should be able to manually slew past the limits. Do that until you have the mount at the right spot to limit it and then use the handpaddle to set the safety limits there. That should take care of that issue.
As for the moon drifting out.
1. That's not unusual because the moon doesn't follow the same path as the stars.
2. if its quite fast are you sure you are accurately polar aligned ( i'm sure you are)
3. do you have the mount turned on
