CT_BuffMod settings are saving fine for me (I'm using Windows XP). You could try using the CT_BuffMod 'reset options' button in the CT Mod control panel (/ct).
The most likely thing that would prevent settings from saving, is if the saved variables file is marked as read only, or if you do not have write permissions on the file or folder. Under Vista, it could be that the saved variable files are in the wrong place, or in more than one place.
Try doing a search for the filename CT_BuffMod.lua (be sure to include hidden files and folders in your search) to see if there are any other copies of that saved variables file on your hard drive. If so, delete the ones you find, reinstall the addon, and try it again. It might be that the game is finding or updating a saved variable file that is located in a one folder, but when the game starts it reads the settings it from a different one.
Here is a link to a thread on the WoW forums which discusses troubleshooting addons under Vista.
http://forums.worldofwarcraft.com/th...sid=1&pageNo=1