Hacking 3DS SD Card files analyse

[Fudge]

OK, so basically I was messing around with the contents of my 3DS's SD card. I have done some tests with Kirby's Dream Land, and here;s what I found.

Replacing .app files will still allow the game to appear in the menu, but not boot.
Editing the CMD still allows the game to boot. I replaced the last 4 digits of Kirby's CMD with HAXX and it still works fine.
Swapping TMDs with Zelda DX (A game I don't own) still allows Kirby to boot. This one really baffles me.

Any insight on why these things happen? The .app one is obvious, but the later two make me wonder.

 

[xblackdemonx]

Replace files on a SD card, BOOM you are a hacker! congratz!

 

[Rutherford Atlas]

Replace files on a SD card, BOOM you are a hacker! congratz!

Come on, now. There's no sense in being so sarcastic. Even simple things like this have the potential to uncover hidden gems that Nintendo overlooked.

 

[Foxi4]

I'm guessing 3DBrew would be the place to look for such information.

http://3dbrew.org/wiki/Main_Page