Wow, old thread!
I will say this, I do small work in aluminum, plastics, etc. and backlash is working correctly in Rev 3.041
I know most say it's not good to use, but I have about .002-.003 backlash on my taig mill and it works perfectly as when engraving tiny little text, (under .100") you can easily see a difference when it's on and when it's off.
Dave