This is a compatibility issue with a feature of the tool, called JavaScript Source Code Protection. This converts the JS files to files that nwjs understands, thus protecting the source code. Since the tool has to patch the engine to load these files, plugins that try to pull their name dynamically don't work. That feature is a dependency for Deep Level Encryption as well, so it can guard the password.
If you don't want either of these, you can disable both of them in the settings (under Asset Preparation). If you do, I cover this here: https://dragonhousehelpcenter.azurewebsites.net/manuals/rmcooktooldx/devguide. On the WindowEx plugin, I see that it tries to pull its name dynamically, so changing the line $_$.params = getPluginParameters(); to $_$.params = PluginManager.parameters('CTB_WindowExMZ') . As for yours, I can't say for certain. But you can create a test build (the option is found on Project Settings, under the essentials tab). First, remove the --disable-devtools from the package.json file temporarily. Then create the test build. Once that's done, press F12 to open the dev console.
EDIT: Wrote the wrong line fix here. And re-wrote the dev tools instructions.