I just got the Altmill Mk2. Been having a lot of issues with it. First thing I did, once I got everything powered on, was work on the spindle. I went with a PWN 80mm water cooled. Oh boy was that fun, but I expected that challenge. I thought that was going to be the hard part. The spindle worked after a couple of work nights tinkering. My next task was just to move X, Y, and Z. Not gonna lie, I was giggling like a kid as I moved the spindle around the table. Then I hit Home. Expecting it to smoothly go home like I see in the videos, it shot back to the far-left slamming into the back end like a train wreck. I was deflated. If I move the spindle out to the open area then hit one of the Go To (on X or Y) I get two inches of travel and then an Alarm 17 error. I have the new sensors with the caps so it’s not a spacing issue. I can manually trip each X and Y1 sensor, so I know they work.
The only way I can get error free movement is to lower the max speed ($110 and $111) from 15000 down to 5000. That can’t be normal right?
Then I accepted my new Lambo is now a Pinto and pressed on. I loaded the Squaring file from IDC and immediately get Alarm 2. 
UPDATE
Totally my fault. It was the dip switches. All X and Y motors had incorrect dip switch settings. The world is a better place now.