First, keep in mind you should only edit JS files that are designed to be edited. This includes the PARAMS files and the KJESiteSpecific.js file. No other JS files should be modified. Doing so may break your calculators. In addition, any changes you make to any other JS file (other than the KJESiteSpecific.js or the PARAMS files) will be wiped out with the application of any future update.
When you edit JS files to include changes to the JS code, from examples below or as instructed by KJE make sure that you follow these basic rules of thumb: