Searching for files on your machine
You can search your machine for files with the name you chose (if you can remember) or for all chart files by typing ".knt2" in your computer search function.
Windows - using Windows 7 and earlier - click your Start menu (round blue icon on the task bar, normally at the bottom left of your screen) and you'll find the search bar at the bottom. Using Windows 8 or above - when viewing your desktop, swipe to the bottom right of the screen to activate a tool bar which has a magnifying-glass icon at the top. Alternatively open a folder and you'll see a search bar near the top right of the window - you may need to change the search location to This PC.
Mac - open Spotlight by clicking the magnifying glass icon in the upper-right corner of the menu bar, or press Command-Space from any app. Spotlight will appear at the front of your screen.