I am not sure what the GitHub version does but this code will take a screenshot and I just tested it on iOS 6 and it works fine.
+(UIImage*) screenshotWithStartNode:(CCNode*)startNode
{
[CCDirector sharedDirector].nextDeltaTimeZero = YES;
CGSize winSize = [CCDirector sharedDirector].winSize;
CCRenderTexture* rtx =
[CCRenderTexture renderTextureWithWidth:winSize.width
height:winSize.height];
[rtx begin];
[startNode visit];
[rtx end];
return [rtx getUIImage];
}
You can call it like this
CCScene *scene = [[CCDirector sharedDirector] runningScene];
CCNode *n = [scene.children objectAtIndex:0];
UIImage *img = [AppController screenshotWithStartNode:n];