The "Layers" preferences (in menu File / Preferences..., "Display" section, "Layers" tab) lets you control the appearance of individual layers, including their stipple patterns.

Each layer has a color and pattern in the top section. You can draw in the pattern area to set a pattern, and you can choose from a set of predefined patterns by clicking on their image below the pattern-editing area.

A layer's color is only editable if it is opaque. When transparent, you must use the "Colors" tab to set the color.

Two sections at the bottom control the appearance of the layer on the screen and on the printed page. The display section lets you assign the layer to one of the transparent layers. You can also choose whether to draw the layer in solid colors or use the specified pattern (and if patterned, you can choose to outline the pattern or not).

The printing section also lets you choose patterned vs. solid and whether to outline the pattern. In addition, it lets you set an opacity which will control its appearance on the printed page.