http://www.4shared.com/file/nhLGDOdd/RocketKnight_ConfigTool_FIX_Mu.html

The Language Selector include the following languages:

English, German, French, Italian, Spanish and Japanese (MULTI6)

Install Notes:
1. Unpack release into your Rocket Knight folder and overwrite
2. Run RocketKnightLauncher.exe (only needed to once if you
want to change to another language)
3. Select language of your choice
4. Play the game