http://store.steampowered.com/app/19030/

Simply set video card AntiAliasing to application controlled:

NVIDIA: Go to "Nvidia control center" (right-click on desktop, Nvidia Control Panel) and set the AA options for application controlled in "Manage 3D settings" or just set "Let the 3D application decide".

ATI: go to "Catalyst Control Center" and set the AA to Use Application Settings.

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