When I connect my JM Badge board to Computer's USB, it runs the message "Press E4 for Bootloader" continuously. After pressing E4 key, left 4 columns of LED light up.
After downloading the .S19 file it doesn't work properly.
It sounds like the main application is broken. The bootloader message "Press E4..." will timeout and attempt to start the application if you do not press E4 soon enough. It sounds like it is trying to start this application and failing, which resets the hardware and it starts over with bootloader. Did you follow the steps as outlined in this post to reprogram the original image?
Retrieving data ...