Wrap your game inside Electron instead of NW.Js.
In Nwjs the files have a small protection when the "package" is created, in Eletron if I want to distribute my game, would it be open or do you have a similar solution?
There is a similar process, tho it is not yet supported. If you plan on using this tool and need this feature, I invite you to file an issue here : github.com/C2Electron/template/issues