First: Create your icons. You will need a png file that is square. It has to be at least 128 by 128 pixels.
Second: Re-size and save icons with the following dimensions in pixels (128, 96, 64, 48, 32, and 16). Name them program_name_icon128.png etc. Also, double check to insure that your .json file references the icons by name and size.
Third: Open Chrome. Go to customize Chrome.
Fourth: Select Settings:
Fifth:
Select Extensions
Seventh: Check Developer Mode and then Click on Load Unpacked Extension.
Finally: Navigate to the file folder where you have your app. Select the whole file folder.
You will then have a local chrome app. When you are done, you can un-check developer mode and close the extensions window. You can launch it, edit and reload it, get details, or delete it.