i Don;t know if that could help , but here is how I made the bottom buttons ( recordarm/solocue/activator) being lit ON one at a time.
Hope this can help .
let me know your other tips and tricks to controls LED from APC40!
PS: on my side, I Didn’t have to activator any mode in Sysex after turning ON the APC with Max, it works instantly , and beware that the tracks selection row sets the channel of all the knobs . Which is very handy in most of cose where you want nto get different scenes layed out on the surface .