With your D1 ON and Connected to XCS
there is a picture of an D1 in the top right.
There is a circle with 2 lines on it.. click on it
In the pop up, click on 'Working Paramaters'
There is an on/off switch next to "Limit Switch'.. Click it off and you are good to go.
You don't want to use the 'Home' function with them off. It will crash into the sides.
Be sure to Frame everything to be sure the piece isn't off center or something.