Unfinished Bits
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Do titlebar/dockwindowhandle so it matches style
Highlight kicker button on mouseover, if possible
Take struts into account in pixelmetric
Appearance of tri-state checkboxes
Palette: need to account for dark and "oddball" schemes
An occasional groupbox is not drawn to style
Draw styled arrow instead of winarrow for general handles

Miscellaneous
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Style listbox panel
Honor frame shapes/shadows/linewidth
Spinbox: draw pressed arrows with highlight
Try to get variable sized pixelmetrics according to default font size

