This tool removes all autoshadows in your game and reflected in the editor.
How to Use: Put this script above main, below materials.
Run your game. Close it.
Close the Editor itself.
Reopen, bam all autoshadows are gone.
EDIT: I tried another one from the same author and it worked. This is the one I used: http://rpgmaker.net/scripts/325/ I'd still like to get this one to work, since seeing the auto-shadows in the editor can be a little distracting sometimes.