When you start the FTB launcher for the first time it asks for an install location this can not include special characters like ' and % but when you later go to the options tab it does accept the special characters. Can this be fixed?
Did you test every MC/FML version found in launcher and what was your "special" character? Current set of allowed characters is tested with multiple versions. Strict path checking makes installation directory selection safer and decreases workload of support persons. (I've seen too many users using ! in installation path and then seeking support because pack launching fails)
Ok I guess it's not that big of a deal as it asks it only once. I was using ' as a character. I don't even remember why I named the folder including that character but it's too late now, I have too many installed programs in that folder
