The dialog control colors are set by the operating system so they match other controls that the OS generates. So in LabVIEW 6, they were actually not behaving correctly.
The following text is from the LabVIEW help on Dialog controls.
"You cannot customize the appearance of the dialog spin control, slide controls, or progress bars because the controls and indicators use platform-specific drawing functions that do not support customization. You also cannot use Property Nodes and Invoke Nodes to customize the appearance of these controls and indicators."
If you need different text color, you'll have to use the non dialog controls.
Ed