You've been bitten by a known bug in the Mach4 soft limits code! Look carefully at the soft limits config screen. For the soft limit min/max settings, the first column in MAX, not min, and the second column is MIN, not max. You entered your min values in the max column, and vice versa. So Mach4 thinks that the max limit is less than the min limit, which is nonsensical The Mach4 jogging motion planner misbehaves and drives the motors the wrong direction. If you try to run GCode (either from a file or from the MDI input), the motion planner will give you an error saying you are outside the soft limits.
So swap the values in these two columns and you should be good to go.
Bob