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New map and asset packages should be saved to UDKGame\ContentSDK. You cannot modify existing Chivalry packages, so when you create or import an asset be sure you don't try to place it in one of our packages.
Creating a new script class
Go into Development\Src. Create a new directory, and within that a Classes directory (see SDKTest for an example). At a minimum, you usually want to create a new Game class, and typically one which that extends from AOCGame or one of its subclasses.
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