Current Features

Loadable Editable Rewritable Expandable
Maps Yes Yes Yes Yes
Dialogue, Events Yes Yes Yes Yes
Music Yes Yes Yes Yes
Music samples Yes Yes Yes No
Font Yes Yes Yes No
Layer 1/2 Tiles Yes Yes Yes No
Tilesets Yes Yes Yes Yes
World Map Yes Yes Yes Yes
Sprites Some Some Some No
Sprite Animations Not really No No No
Character Stats Yes Yes Yes No
Misc Numeric Data Some Some Some No
Enemy AI No No No No
Sound Effects A bit No No No
Menu/Misc Graphics Sorta Sorta Sorta No
Title Screen Yes Kinda Kinda Not really

Dependencies

Place these in the same directory as the executable. Note that you only need one FMOD DLL or the other.
FMOD for x86 - FMOD audio playback DLL for x86
FMOD for x64 - FMOD audio playback DLL for x64
OpenTK DLLs - OpenGL for C# [Build 0107 and older only - no longer used in newer builds]
 

Builds

Latest release notes
Build 0213 - 05/29/2014
Build 0212 - 05/17/2014
Build 0211 - 05/11/2014
Build 0210 - 07/20/2013
Build 0208 - 07/18/2013
Build 0207 - 07/18/2013
Build 0206 - 07/16/2013
Build 0205 - 07/01/2013
Build 0204 - 06/30/2013
Build 0203 - 06/29/2013
Build 0202 - 01/23/2013
Build 0201 - 01/20/2013
Build 0107 - 01/08/2012
Build 0106 - 01/07/2012
Build 0105 - 01/03/2012
Build 0104 - 12/17/2011
Build 0103 - 11/24/2011
Build 0102 - 11/21/2011
Build 0101 - 11/19/2011
Build 0100 - 11/19/2011

Links

Blog - Various updates and screenshots
Board at ACMLM - Discussion board for Secret of Mana Editor and SOM hacks.
Old board - With my bug listing