I think Homing also works but I prefer not to do things like that.
I had a front turret and also a rear turret. As my rear turret was default then I just used Rear tools in the tool table and set the offsets up accordingly. Worked ok but you just had to use negative values for X when using tools in the front. In code that did not have negative X values I inserted a G51X-2 before a front tool and G50 to cancel, was a pain but it did work until you forgot to cancel before a tool change
I then got Dolphin CADCAM and made a custom PP for it, the X values were correct for any code it produced.
As for not being aboe to use Mach, well I think EMC is similar in that respect or at least it was what I was told when I enquired regarding front/rear tools, I was told just programme neg x values where appropriate. As that was the same as Mach there was no benefit to change.
Hood