Why does my CS6 units & measurements show comma for decimal symbol? I expected it to be a dot. After reading elsewhere on the Internet, I made sure that my system preferences are set to English. See screen shots below.
Mac (10.8.2) > System Preferences > Region setting
InDesign CS6 (example: see the value in the Width field; it show "8,5 in" instead of "8.5 in".)
My gut feeling is that you are a Creative Cloud user who has the wrong localization. Are you in Canada? More to the point, are you in Quebec? Are you a Creative Cloud user? If so, I'm vague on the details, but it seems like you can download pretty much whichever localization of ID you want. If you have an ordinary desktop license, then what region is it for?
Lastly: OS X applications in general tend to respect the system settings for region and units, but I would be unsurprised to learn if (some) Creative Suite applications did not.
I understand your question entirely - I must have asked my own in a way you don't understand. This kind of problem (getting the European-style comma as decimal separator instead of the North-American-style period as decimal separator) might be fixable in a variety of ways, depending on how which variety of InDesign you have already installed. Are you a Creative Cloud user? If not, then in which country did you buy your InDesign/Creative Suite license?