I've setup a document template, specifying the color mdoel as CMYK. To check it is OK, I did a File, New from Template, chose my template and checked the File > Document Color mode. It correctly says CMYK.
Then I drew a rectangle, went to the Appearance panel, and clicked on the little white square next to Fill: . A mini palette opens up, but when I hover the mouse over a color swatch, it pops-up RGB values! However, if I shift-click that little white square next to Fill:, I correctly get shown CMYK sliders. Why is the little palette popping-up RGB values when the document is defined from the start as being in CMYK mode? (Note: I'm sure that hovering over the palette was popping-up CMYK values some time ago....)
In searching for an answer I've seen references to "the default startup profile", but have no idea where this is or how to adjust its settings (if it's relevant anyway).
I believe this is what you're searching for... I stand to be corrected if it's not.
My Computer > Local Disk (C:) > Program Files > Adobe > Adobe Illustrator CS4 > Support Files > Required > New Document Profiles > en_US > Basic CMYK.ai or Basic RGB.ai
In that case, I wonder what all those profiles are doing in: \Documents and Settings\<username>\Application Data\Adobe\Adobe Illustrator CS4 Settings\<yourlanguagecode>\New Document Profiles? That's where I put some new files of my own and they appear in the New Document Profile box on the File>New window...