maxMasterSlaveDistance question

Hi,

I am setting up the cnc760 on an Avid cnc, which is a fairly flexible (not rigid) router. The setup has been fairly straightforward and nice so far.

I see that my maximum slave axis distance is set to 100 (what units?)by default.
I tried to set it higher, it did not allow, once saved it returned to 100.
I then changed the variable in Server.ini, but that does not effect a change either.

The machine was homing well during testing at 100, now it fails every time with a warning. I even prepositioned the Y axis' before energizing, just right, to see if I can get it to accept, but it does not. Why it fails every time now, I am not sure, anyhow.

How can we bring that variable up? My gantry can flex 2cm easily, once energized on servos, it is an adequately stiff machine, but when off it does not mechanically suit the tolerance of this variable. Please advise, thanks.