On my machine at home, pressing the left arrow button on the keyboard results in Mach3 moving the milling table to the left.

On the Tormach PCNC 1100 at work, pressing the the left arrow button results in Mach3 moving the milling table to the right.

Which configuration of travel is preferrred or correct?

Bob

Tormach is correct. What you need to think of is the direction of the cutter in relation to the work piece. On a moving table machine the table will move right but the cutter is moving negative in relation to the work so left arrow moving table right is correct.
Hood

Hood,

Thanks !

Bob