Keith,
You should have done no harm at all. You can always run a notch higher octane. In aviation, we are even taught that if your plane takes 80, and they are out of 80, ask for the next grade up. But obviously never trade down octane ratings.
I run 100 octance in my race car, which is a stock motor, as it actually burns cooler than 93 octane, and results in about 10-20 degrees fahrenheit lower engine temps. That is the #1 reason we run it when we race. (Isn't the smell great
??) If you were to tweak timing, etc, you would have more play without risk of detonation and then maybe more power with the higher octane. Without a change of engine settings, I would not expect any HP gains without an electronic computer, but there are others who likely know more. But as it was, you should have done no harm.
Without seeing the coolant thing, I don't know what to say other than I am sure you would have some pooling in certain horizontal areas within the block of coolant.