Arima - if your game is already offline (e.g. node-webkit), then there is nothing to download. As above, there may still be pauses between switching layouts not because anything is being downloaded, but simply because loading all the images in to memory can take a moment. And to clarify, layout-by-layout memory management means it does not load the entire game to memory on startup, only the first layout, and when you switch layout it only loads the next layout's images, and so on.
Ashley - Sorry, I suppose I wasn't clear - I'm aware of what you stated. By "Loading an entire large downloaded game" I wasn't referring to downloading assets from the internet when running a node webkit game, I was talking about a node webkit game that had been downloaded before running, and loading all of the assets from disk at once at the start being unnecessary, increasing startup and preview times, since as I understand it even with layout by layout loading, all files are loaded into ram at the start, they're just not all loaded into VRAM on the GPU at once.
Also, with the actions I mentioned before, I was theorizing that in addition to the action to preload assets from disk, there could also potentially be an action that could preload stuff to the GPU like CC had, which could be used to eliminate that pause. Perhaps this is better wording:
Use offline cache: on (same as current, loads or downloads everything at start)
Use offline cache: off (loads or downloads files of only the first layout)
Preload layout assets to RAM - downloads from Internet or loads from disk, depending on platform. Happens invisibly behind the scenes
Preload layout assets to GPU - sends assets of a layout to the GPU. If the files have not been downloaded or loaded from disk yet, they are downloaded/loaded first.
And triggers for each when they're done.