I've just upgraded to Take Command 21.01.47 x64 (on Windows 10 Creators Update). After selecting Options -> Styles -> Theme -> Office 2007 Blue, the theme seems to change succesfully. However, after exiting Take Command, and then starting it up again, the theme is weirdly broken, and several parts of the UI are apparently not redrawn at all: It's as if only parts of the theme were applied. This strangeness only applies to the Office 2007 Blue, Silver, Black and Aqua themes. I could reset the theme by deleting the OfficeTheme value under HKEY_CURRENT_USER\Software\JP Software\Take Command 21\Settings, so I've reverted to using the Windows 7 theme for now.