Sage web screen customisation

Does anyone know how to customise Sage 300 web screens to run custom functions eg. auto print warehouse pickslip, email customer invoice and end shipment file to 3rd party warehouse when the O/E order entry post button is clicked. On the desktop version I use vb6 to create these kinds of customisations, but am struggling to get an answer on how this could be done with a web screen. Any help appreciated.