As I noted in my earlier post, the method for selecting theme (‘accent’) colours in Windows ‘Blue’ build 9364 has changed from Windows 8 RTM. I’m not going to bother looking too closely at the updates to the functions in UxTheme.dll this early in the development process, but I did notice two new registry values in the key HKCUSoftwareMicrosoftWindowsCurrentVersionExplorerAccent: ‘AccentColor’ and ‘StartColor’. These are DWORD values that store the accent colour and background colour, respectively. The format is 0xAABBGGRR. The old ‘ColorSet_Version3’ value from Windows 8 is gone for obvious reasons. ‘AccentId_v8.00’ from Windows 8 is now ‘MotionAccentId_v1.00’, but it seems to serve the same purpose – indicating which background image is selected.