I have installed the app, messed with the colors then I uninstalled it.
Opened MS Health to get my old color setting back, but the Band is still stuck with the color settings of BandSocial.
Strange! I tried the same steps few times and I was able to reset my theme back with the MS Health App. Also if you close and reopen the App, it will show one of the default theme color and you can set it.
Yes.
BandSocial only allows tiles customisation. In order to be relevant, you need to go the extra mile and allow color customisation for the Me tile too.