I recently picked up a Neo Trellis M4 and began playing with it. As I was poking around online looking for projects that have used I ran across this Adafruit Learning Systems Guide for a NeoTrellis M4 Launchdeck. This nifty little thing caught my attention so I got the code downloaded and running on my trellis. As I was about to start editing the config dictionary to setup my various launch keys and macros I thought "Hmm what if there was a basic GUI that you could use to configure this. You could even see and setup the colors for the neopixels. That would be neat". This thought caught me in just the right way to send me down the rabbit hole. I wound up working on this page until it was functional before I even configured the launchpad for the first time.
This page lets you import your configuration by copy/pasting it from your code.py file. Then you can edit the colors, keys, and even comments for each of the trellis buttons. Once your done you can export it back out by copying a python keymap dictionary definition out of the page and back into your code.py file.