Firstly .. Uncheck reference to CustomListView Library , you have included the class module instead (.bas)
Next , in the CustomListView Class Globals edit sv AS ScrollView as Public
Then in any module you can call ..
Log(ListView_Order.sv.ScrollPosition)
The error you are getting refers to unmatched sub signature ... Check that the parameters of Sub Create_OrderList matches those you are sending.
Personally i would have populated an map and passed that instead for easier reading.