Shopbot Buddy Alpha 48
I get this window pop-up when I try to load a part file or run a homing macro.

Use Arrow Keys to move Off of Prox Switch (ESC when Clear)

My proximity switches glow red, when over the nut the light goes out. Behavior replicated with a screwdriver.

Limits are set to ON
Input switch #2 and #3 are set to Nrm Closed Limit

Before I power up I pull the carriage and table to the hard stops.
Turn on the control box
Hit the reset button
Start the software
z3 followed by zt
move .5, .5, 1 and redo z3

Load a part file and it reads through some number of lines and then I get this:
Use Arrow Keys to move Off of Prox Switch (ESC when Clear)

More info:
The input read-out in the red window shows this
#1 unlit and green
#2 lit
#3 unlit and yellow
#4 unlit and red