Mopidy Discourse

Problem with power button & LED status indicator

Have anybody succeeded in applying Howchoo instructions for Raspberry Pi power button and LED status indicator to PiMusicbox?
I mean these two:

My experience is that the power button works but is not reliable. Sometimes it just doesn’t stop the musicbox running.
However, the status indicator does not work at all: adding the required code to /boot/config.txt crashes the musicbox.
I just would like operate the musicbox hardware without ssh.