hm... I cannot see why this should be happening at all. But I'm inclined to just remove the break_edges references all together.

Fredo, Thanks for the heads up on the ones in your collection. Inside the Joint Push Pull folder I found the line to modify so that one is working again also. On my Mac have never been able to set shortcuts for toolbars inside SU. I usually work with only one row of toolbars down side and toggle on and off as needed. I assume the problem began when I installed Snow Leopard as was problem free in this regards beforehand. Many thanks for your tools.

You can make various styles that would have the back edges displayed. They can't have any of the raster-based edges. As long as you are okay with the basic edge settings, back edges can be used in styles that have watermarks. I have found that if you have back edges checked on, the setting will be lost if you switch the display styles to transparent. Toggling off the transparency will not reinstate the back edges. To get them again you need to turn them back on in the style's edge settings (or apply a style that has the setting on). I'm guessing this could be a bug. I'll report it to Google.