Waaayellll, I think I'm skirewed. Both of your directions lead me to that final key door, and that's where I am short. I found one key in the overworld, and a couple of "keeyees" (don't know what they're for, nor do they show up in my subscreen). I had gone to the Dream Palace, before finishing lvl 7, and that's where I probably used one too many keys. Not managing the keys very well . So if you know where a few more "true" keys are in the overworld, please pm me. Thanks!
There is a spare key in level 5 under the water, if you haven't already gotten it. From the entrance go up three screens and left one screen.
Also, you can get the magic key if you've gotten through Level 8:
Edited by RetraRoyale, 24 July 2013 - 08:49 PM.