Re: floating bridge
I agree totally with JohnJohn's procedure. When you said you did it in a half an hour, my head spun and I said, "naaah." But now that you mention that you didn't do any adjustments to the springs or the truss rod, I understand. Like JJ said, you could still play it that way (Eb), but your Floyd will be pointing up in the air slightly, and if your action was set real low to begin with you might experience some buzzing, and your intonation would be off to some degree.
If you go back to your standard E setup, your guitar should spring back fine, but then again Floyds can be touchy things. Also, going back and forth shouldn't hurt it at all as long as you go easy on the truss rod and only turn it an 1/8th to a 1/4 turn per day.
My Jackson is funny in that it needs an adjustment about twice a year, changes with the seasons and the humidity. I have to adjust the truss rod and the Floyd every 6 months or so.
Hope this helps.