Before you locked it it would have been set around 8*, and then it would mechanically advance (what you just de-activated) from there.
With the locked dizzy you should be running around 20-25*, because it no longer advances.
So, you shouldn't have done any damage, it would have just been running way worse than it should be.
Oh and just a word of warning - Motors with locked dizzy sometimes don't like starting on a cold morning (because you only need like 0-5* to start, not 25*), they'll wind over really slow to start with and finally kick into life. Its no biggy and will still start, just now you won't be suprised when it does. :wink: