For references here is my code to change from X,Y axes to X,Y,A,B axes
------------4 Axis Mapping-----------
inst = mc.mcGetInstance()
local xAxis = 0
local yAxis = 1
local aAxis = 3
local bAxis = 4
xAxis = tonumber(xAxis)
yAxis = tonumber(yAxis)
aAxis = tonumber(aAxis)
bAxis = tonumber(bAxis)
--motorId, rc = mc.mcAxisGetMotorId(number mInst, number axis, number childId)
local motorIdX, rc = mc.mcAxisGetMotorId(inst, 0, 0);
local motorIdY, rc = mc.mcAxisGetMotorId(inst, 1, 0);
local motorIdA, rc = mc.mcAxisGetMotorId(inst, 0, 1);
local motorIdB, rc = mc.mcAxisGetMotorId(inst, 1, 1);
--rc = mc.mcAxisUnmapMotor(number mInst, number axisId, number motor)
mc.mcAxisUnmapMotor(inst, 0, motorIdX) --Unmap from X axis
mc.mcAxisUnmapMotor(inst, 1, motorIdY) --Unmap from Y axis
mc.mcAxisUnmapMotor(inst, 0, motorIdA) --Unmap motor 2 from X axis
mc.mcAxisUnmapMotor(inst, 1, motorIdB) --Unmap motor 3 from Y axis
--rc = mc.mcAxisMapMotor(number mInst, number axisId, number motorId)
mc.mcAxisMapMotor(inst, 0, 0) --Map motor 0 to X axis
mc.mcAxisMapMotor(inst, 1, 1) --Map motor 1 to Y axis
mc.mcAxisMapMotor(inst, 3, 2) --Map Motor 2 to A axis
mc.mcAxisMapMotor(inst, 4, 3) --Map motor 3 to B axis
--rc = mc.mcAxisEnable(number mInst, number axisId, number enabled)
mc.mcAxisEnable(inst, 3, true) --Enable A axis
mc.mcAxisEnable(inst, 4, true) --Enable B axis
--rc = mc.mcProfileSave(number mInst)
mc.mcProfileSave(inst)
-------------2 Axis Mapping-------------
inst = mc.mcGetInstance()
local xAxis = 0
local yAxis = 1
local aAxis = 3
local bAxis = 4
xAxis = tonumber(xAxis)
yAxis = tonumber(yAxis)
aAxis = tonumber(aAxis)
bAxis = tonumber(bAxis)
--rc = mc.mcAxisUnmapMotor(number mInst, number axisId, number motor)
mc.mcAxisUnmapMotor(inst, xAxis, 0) --Unmap motor 0 from X axis
mc.mcAxisUnmapMotor(inst, yAxis, 1) --Unmap motor 1 from Y axis
mc.mcAxisUnmapMotor(inst, aAxis, 2) --Unmap motor 2 from A axis
mc.mcAxisUnmapMotor(inst, bAxis, 3) --Unmap motor 3 from B axis
--rc = mc.mcAxisMapMotor(number mInst, number axisId, number motorId)
mc.mcAxisMapMotor(inst, xAxis, 0) --Map motor 0 to X axis
mc.mcAxisMapMotor(inst, yAxis, 1) --Map motor 1 to Y axis
mc.mcAxisMapMotor(inst, xAxis, 2) --Map Motor 2 to X axis
mc.mcAxisMapMotor(inst, yAxis, 3) --Map motor 3 to Y axis
--rc = mc.mcAxisEnable(number mInst, number axisId, number enabled)
mc.mcAxisEnable(inst, aAxis, false) --Disable A axis
mc.mcAxisEnable(inst, bAxis, false) --Disable B axis
--rc = mc.mcProfileSave(number mInst)
mc.mcProfileSave(inst)