CSS Sculptor screen.css file problem

If I use CSS Scluptor 3 to add a tabbed panel and use an image for the tab or change the size of the tabs CSS Sculptor generates SpryTabbedPanel definitions in screen.css which overides any changes made in SpryTabbedPanels after that.

For example if I use CSS Sculptor to add a SpryTabbedPanel then I make modifications to it, specify an image file for the tab or change the size of the tabs, then I generate the page. Now I go into SpryTabbedPanels.css and add my definitions for the tab, tab hover, and tab down and change the tab size etc. Nothing works because of the definitions in screen.css are overiding everything in SpryTabbedPanels.css

If on the other hand I use CSS Sculptor to only add a SpryTabbedPanel and make no modifications to the tabbed panel and generate the the page and then afterwards I go into SpryTabbedPanels.css and add the images and any other modifications I like then it works fine. This because as long as I make no changes to the tabbed panels in CSS Sculptor then no SpryTabbedPanel css definitions are generated in the screen.css file. So since nothing is overiding the SpryTabbedPanels.css then everything works as it should, just as if I had added the Spry Panels on my own and not used Web Assist CSS Sculptor to define tabbed panels at all but add them after the page is generated.