I think there is a bug with scale when using zwoptex texture/plist with offsets in combination with CCSpriteSheet (cocos2d 0.9 beta). Here is simple code:
[[CCSpriteFrameCache sharedSpriteFrameCache] addSpriteFramesWithFile:@"testing.plist"];
CCSpriteSheet *sheet = [CCSpriteSheet spriteSheetWithFile:@"testing.png" capacity:10];
[self addChild:sheet];
CCSprite *sprite = [[CCSpriteFrameCache sharedSpriteFrameCache] createSpriteWithFrameName:@"spr1.png"];
sprite.position = ccp(160,240);
[sheet addChild:sprite];
id action1 = [CCScaleTo actionWithDuration:5 scale:0];
[[CCActionManager sharedManager] addAction:action1 target:sprite paused:NO];Watch the animation and you'll see strange behavior. spr1.png is 320x480 image with most pixels transparent, so when trimmed in Zwoptex, there are offsets. Same code works ok if sprite isn't added to CCSpriteSheet but to scene/layer for example.
I don't think you need actual images to test this, just use any zwoptex texture with offsets...
