Axes parameters
Robot controller can use external axes and it is necessary to assign correct positions (indices) for these axes in the assembly. Default SprutCAM postprocessors use index-based axes identifiers (ExtAxis1Pos for the first axis, ExtAxis2Pos etc). Some custom postprocessors can use axis address instead of indices (E1, E2, E3, J4 etc).
Click 
button to open the Assembly parameters panel. Then go to the Axes tab.
Define Address and External axis position (index) here. MachineMaker will show axis identifier (like ExtAxis3Pos) in tooltip. You can use it in the postprocessor.
Axis address and axis index must be unique in the assembly context. If you try to set use a value that has been already taken, MachineMaker will propose to replace the existing one.
It is not possible to change the robot axis address and index. You can change external addresses only.
It is also possible to define additional axes parameters here: Control type (Continues, Indexed, Manual), Brakes and Shortest path rotation mode.