Hello, I have a problem when running a script to Z Auto Zero Tool, although I put a lower value the minimum speed is always 130U/min (milimeters).
Another problem is GetVar seems to not work with my motion board properly, take the measure of the previous run if it really works.
GetVar is not too important if I get it to work at a slower speed.

Board - DDSM3V5 (purchased in China with a technical support bad or nonexistent)

This is the code, I tried some modifications without result.
-------------------------------
Sleep 2000
ZT=GetVar(2002)
Code "G90 G1 F50 G31Z-250"
While IsMoving()
Wend
Sleep 500
Code "G1 Z" &ZT
While IsMoving()
Wend
SetDRO(2,10)
Sleep 500
Code "G0 Z50"
While IsMoving()
Wend
Code "G90 G1"
Message( "Z Axis is now zeroed" )
End
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I think you have discovered the problem.

Most, if not all, of the Chinese motion control boards fail to implement the GetVar function. 

Tweakie.

That does not explain the high feed rate with G31 command or maybe yes.