Hi dune1982, it looks like the error report is off, the actual error is 2 lines down from GetObjects(), here:

linelist.addObject(objectpicker);

ObjectList.addObject() expects a geomobject while that is passing an objectpicker instead. Also further down for the setInput call I think you need to pass just linelist since it is an objectlist, linelist.objects would be an error.

So something like this:

//Will do the intersection 
function DoIntersect()
{
	
	var objectpicker = moi.ui.createObjectPicker();
	//objectpicker.min = 2;
	
	if ( !GetObjects( objectpicker ) )
	    return;

	var picked_objects = objectpicker.objects;

	for ( var i = 0; i < picked_objects.length; ++i )
	    linelist.addObject( picked_objects.item(i) );
	
	var factory = moi.command.createFactory( 'intersect' );
	factory.setInput( 0, linelist );
	
	factory.commit();
}

DoIntersect();