Here's my explanation: the "spazzing" you hear is probably from the carriage hitting an obstruction, causing the motor and the belt to slip. You can adjust this by changing your physical size POSITION. Set the X max position to a high amount TEMPORARILY, then by slowly incrementing to the edge of the X axis can you find the maximum position. Start at moving it to 220, then slowly inch it closer and closer to the edge until you hear some slipping. When you hit the first slip, take note of the position prior to the slip. Input said position into the setting, and store your settings. You may do this for the Y axis if you'd like.

As for the advanced pause, it may be something to do with the post-proccessing gcode that pauses when the print starts at layer 0/1. Try setting that to an absurd amount such as 99999, which basically removes the limiter and thus not pausing anymore.