If you add this as a source in BSE instead of a downloaded XML file
Code:
http://www.icetv.com.au/cgi-bin/epg2/iceguide.cgi?op=xmlguide&desc_length=0&user=xxxxx&pass=yyyy
BSE will grab the xml for you. You don't need to schedule WebGet then. Obviously you need to add your username/password combo into the URL.