Green Flag in The Great Maze (Super Smash Bros Brawl, SSE)

So, as you probably already know, in Super Smash Bros. Brawl, the Subspace Emissary, there is a crown on a level if you have gotten all the gold boxes in a level.

I have double, triple, and quadruple checked against 3 different guides for gold boxes in The Great Maze in SSE. I have gotten all of them. Yet, I still have a green flag in the bottom left corner of the Great Maze. I don't know WHAT I'm missing. Could somebody help me? Thanks!

I have also beaten the game, so I have access to all rooms.

Orange cubes aren't the only part of whether a level is fully completed. There's also:

• All characters have been unlocked
• All doors have been opened
• All trophies/collectibles out in the open have been collected

I believe you have to complete the level for any of these to count; collecting and quitting won't do anything.