<font face="Arial, Verdana">Came here looking for the same solution, Being able to individually change the steps for mm on a per motor basis.I'm having issues with the Z level between the towers being lower than at the towers.</font>
This thread says the error is a relationship between steps and Diagonal rod length and explains a iterative process to address it.
<font face="Arial, Verdana">http://forums.reprap.org/read.php?178,492382</span></font><br/></div><div><font face="Arial, Verdana">
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<font face="Arial, Verdana">I checked my steps and found two towers to be out a little (80.5 steps/mm).</font>
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