Your internet service does not need to be working to use the web interface, and if your router does not support netbios then you can hard-code an IP address for the printer in config.g and then type that IP address into your browser address bar.
However, it should be entirely possible to control the printer through Pronterface. The main thing you need to know is that sending G32 through Pronterface is equivalent to pressing the Auto Bed Compensation button on the web interface. Also you need command M555 P2 in config.g, but you probably have that already.
Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod
Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].