Alright, I beat it. That level nine was brutal, even with the red tunic. It was otherwise a good level, though the flashing floor could be painful in a few places. I mean if you time it well it's fine, the only real time it gave me a problem was in the boss key room, but that was because of the difficult-to-kill enemies. And by that I just mean the fire bats that can only be killed by the Gust Jar. Unless there's another way to kill them and I just wasn't paying attention. Still, all in all, pretty good quest, I'm gonna put a comment on it soon and hopefully can squeeze all my thoughts into it.
One thing I'd point out in the credits: You spelled Radien's name wrong.

There's also what appears to be graphical errors on this credits screen, spoilered because credits:
And yeah, apparently that was the Trial of Power I snuck into and beat, because I got the Trial of Power item instead of Nayru's Love; didn't pay attention before. So that was due to that bug Air Luigi found.