Following the instructions in uDig Walkthrough 1 for creating a map results in a zero extent map. Workaround is to select a layer and hit zoom to extent.
1.Create a New Map, and press the tab for the Web Catalog view (located along the bottom of the window near Catalog).
2.Click on the WMS link for dm solutions.
3. The Add Layer wizard will open (uDig can recognize links to spatial content). Choose the Parks, Provincial Border, Roads and Cities and press Finish