You can create your own customized Multipart Path following the above mentioned way .There is one more way by which you can do the same. If you are facing problem in only passing the point to the MPP then you can you use this command "leDefineMPPTemplate" . Here you don't have to pass the points, it will work in interactive mode just like during drawing a path user is able to see the path.
Basically "leDefineMPPTemplate" and "rodCreatePath" command's syntax are similar
Syntax of "leDefineMPPTemplate"
?name Multipartpath_Name ; it should be a string
?layer list("prBoundary" "drawing") ; Master layer name normally set it to peBoundary
) ; end of leDefineMPPTemplate
Syntax of "rodCreatePath"
Points=list(list of points)
?name MPP_Name ; it should be a string
?layer layer_name ; this is the master layer name
?width layer_Width ; master layer width
) ;end rodCreatePath
only difference in "rodCreatePath" is you have to pass the Points of the MPP to the ?pts field, which is done by enterPath() function.
I hope this will solve your problem.
please refer "sklayoutref.pdf" to learn more about these commands