Cocos2d question

[VinC_HK]

screenSize = [[CCDirector sharedDirector]winSize];
bgImg = [CCSprite spriteWithFile:@"Texture/ChessGame/BackGround.png"];
bgImg.position = CGPointMake(screenSize.width * 0.5f, screenSize.height * 0.5f);
[self addChild:bgImg z:5];

cube = [CCSprite spriteWithFile:@"Texture/ChessGame/Cubes.png"];
cube.position = CGPointMake(screenSize.width * 0.5f, screenSize.height * 0.5f);
[self addChild:cube z:5];

CCSprite *grass = [CCSprite spriteWithFile:@"Texture/ChessGame/grass.png"];
grass.position = CGPointMake(screenSize.width * 0.5f, screenSize.height * 0.5f);
grass.scale = 0.5f;
[self addChild:grass z:11];

[cube runAction:[CCSequence actions:[CCDelayTime actionWithDuration:3], [CCLens3D actionWithPosition:CGPointMake(screenSize.width * 0.5f, screenSize.height * 0.5f) radius:240 grid:ccg(50, 50) duration:0.1f], nil]];

there are 3 sprite here, the second sprite with the cclens3d effecs, but after running the apps, all the layer of the sprite have a full black screen, and block the sprite under it, any method to solve this problem?