To choose a fill pattern, select the layer or the layers for which to change the fill pattern and choose the fill pattern from the "Stipple" panel.

New pattern can be created with the "Custom Pattern" button. A pattern editor will come up that allows creating and editing of new pattern. The predefined pattern cannot be changed. To apply a new pattern, select "More" from the pattern selection panel and choose the new pattern from the list. The custom pattern are saved with the layer display properties.