OK. Update. It doesn't seem to be tied to the NW.js version. In fact, the HTML export is acting similarly. Reading the logs as it loads, it appears that the game is loading every single layout's images at the start-up. Any idea why this would be happening?
As another weird side note; I was able to export an NW.js version that runs properly by unchecking the preload sounds. (It runs the initial layout at 700 MB instead of 4 GB) We have a lot of sounds, but I have no idea why this would affect the game in such a way.
As usual, any ideas at all are utterly appreciated!