Hi Jim,
You got it right.
Your registration no 2 cannot find the style that initially was saved in that registration, so the keyboard just continues to play the last style that was already uploaded.
In other words,it isn't registration 1 that is still playing when you press reg 2.
It is registration 2 that is playing BUT with a "missing" style in it, so it plays the last one, whatever that was.
Find the style,resave the registration and don't move the style to another folder because you will have the same problem again.