WHy does your X1*90 move not work

Easy you are trying to do an inc move with an abs position value NOT an inc value.
Take this example. Lets move to teh far side of the table so the example will be dramatic. Teh hole you are probing is 1" diam
Your first leg of the probe doing a center of circle trips at X95. So that makes your X 1 = 95.0000 OK X3 = (95.0000 * .90) = 85.5
Your routine is STILL in INC mode so when you go to Code"G0 X "& X3 it will MOVE right 85.5 " AND you just broke your probe.
HAD you actually been testing as you created each line you would have seen this right off teh bat (;-) .
Also I did not finish the Formula to find center of a circle for a reason. It was to make you think about what you were creating.
There are 2 basic ways to work teh formula. From an INC approach OR ABS approach. THAT would be your choice . But each takes a different way of doing it.
You are missing a LARGE block of basic knowledge for using Gcode. Trying to create a high end macro WITHOUT that knowledge is like trying to do Algebra without understanding the basic rules of Algebra. It will not make any sense.
(;-) TP