[Closed] Source channel in projection modifier type

Hi,

I’m creating a projection type via:

theObj.projection.addRegisteredProjectionType 1
theHolder = theObj.getProjectionType 1

But i can’t seem to find a way to change the source channel to ‘Vertex Position’, calling:

theHolder.sourceMapChannel = 5

Does’nt seem to do anything, and I’m guessing this is to do with map channels rather than the radiobutton selection.

Any help is greatly appreciated,