Sorry to be late getting back to you. (Patients...and patience
).... Theme Manager is buggy, and we've been promised a fix, but I guess it's one of those things that're "still in the works".
As for "Control Center", that went the way of the dinosaurs and isn't compatible with your OS. I agree that a flag/pop-up would be nice, also...that Impulse sense your OS and not make incompatable available on the list in the software tab.