Ah, I see where I failed. I hadn't actually implemented the SteamworksPlus_SteamUserStats.js, since the translation plugin had all of the plugin commands for achievements I didn't think I was missing anything.
However, when I add SteamUserStats.js, I now am unable to boot the game in steam. No error message, just a loading screen that spins endlessly. If I disable the Steamworks plugins, it works fine. This is with the Electronjs version.
I went back and tried again with the NWjs version with all of the changes I've made, but then I get the initial Node error again. I'm going to try to go through the steps again with the Electronjs version...
EDIT: Tried again with the Electronjs version, still get the infinite spinning circle...