Intro

You might assume that Node Webkit, or NWJS as it's now called, would support flash out of the box or in a simple straight forward way, but it does not.

You can find some of the information needed from a google group discussion. Additional information is contained in a github issue

Below are the steps I used to solve the issue.

Download Flash

• Install https://get.adobe.com/flashplayer with the PPAPI option
• Navigate to C:\Windows\System32\Macromed\Flash
• copy C:\Windows\System32\Macromed\Flash to .\PepperFlash\ in your nw folder

Modify NWJS Application

• Add the following code in your NWJS application

chrome.contentSettings.plugins.set({
    primaryPattern: "<all_urls>",
    resourceIdentifier: { id: "adobe-flash-player" },
    setting: "allow"
});