SpriteKit unarchiveFromFileは、アセットカタログおよびアトラスからテクスチャをロードしません

私はまだSpriteKitを初めて使用しているので、XcodeのSKSエディターを使用してレベルを作成できるかどうかを確認したいと思いました。「Spaceship.png」テクスチャを使用してスプライトをいくつか追加し、テンプレートアプリを作成すると、テクスチャが読み込まれません。

これは、言語としてSwiftを使用し、提供されている「Spaceship.png」スプライトを追加したバニラOSXゲームテンプレートのスクリーンショットです。テクスチャはきれいに表示されます。テンプレートを変更しただけでアプリをビルドして実行した結果は次のとおりです。

The debug console displays this warning message: I tried to add an .atlas folder, and got the same result. the scene just displays the red X icon in place of the sprite. If the added sprites where just color sprites, they display fine. I had an app some time ago that I scrapped, where I used to load the SKScene and would manually add the sprite assets within to my SKScene sub-class, and it worked fine.

If, however, i moved the textures - "Spaceship.png" as an example - to the root of the project, i.e. not inside an asset catalogue or .atlas folder, the scene loads with the textures displaying fine.

Here's the texture added to the root of the project:

And this is the desired result: I tried to manually add the loaded assets from the SKS file to the scene via enumerateChildNodesWithName(_,usingBlock) and I get the same result if the textures were not in the root of the project folder.

This is me trying to add the assets manually:

    func applicationDidFinishLaunching(aNotification: NSNotification) {
    /* Pick a size for the scene */
    if let scene = GameScene.unarchiveFromFile("GameScene") as? GameScene {
        let sceneToBePresented = GameScene()

        /* Set the scale mode to scale to fit the window */
        sceneToBePresented.scaleMode = .AspectFill
        sceneToBePresented.size = scene.size

        /* Sprite Kit applies additional optimizations to improve rendering performance */
        self.skView!.ignoresSiblingOrder = true

        self.skView!.showsFPS = true
        self.skView!.showsNodeCount = true
        scene.enumerateChildNodesWithName("*") { node, stop in
            sceneToBePresented.addChild(node.copy() as SKSpriteNode)
        }

        self.skView!.presentScene(sceneToBePresented)
    }
}

I looked around SpriteKit classes - SKNode, SKScene, SKTexture, SKSPriteNode - for any clue about paths, caching, preloading, or anything but was unable to find a thing that could make this work.

I am running Xcode 6.1.1 and my target is 10.9, and the language I'm using is Swift, although the same behavior holds true using ObjC. Is this a feature or a bug? Anybody else running/ran into a similar situation ?

Thanks in advance for any help

[UPDATE]

Looks like this is not implemented yet - loading textures from asset catalogs - as this post in the dev forums discusses the same issue, and his solution is to rename the asset catalogues to be the same name as the texture. In essence, what I found out about having the image files in the root folder: How do you load sprite textures from Images.xcassets when using SKS scene file, although my earlier app which i managed to roll-back to a working state does load textures from .atlas'es, but i can't seem to do it with a clean template!!!