Yep, one can only adjust, when the device is powered on & yeah, be aware of static electricity — I did the same . . . It’s also better to keep the AK powered on for a while, before adjusting the contrast.
I meanwhile sold the Analog Keys, as this solution is temporary + the frustration of working on such a display didn’t go away. It’s a major design flaw affecting all devices using the same display.
It seems to depend on the condition of your/the display — you may turn on the Analog Keys (or any machine with this generation of crap display) after a while, and the adjusted contrast won’t be the same as right after the adjustment. Mine shifted towards an overall darker and blurry effect, yet it certainly is an improvement, so it’s still worth the effort.
I did the same for my Analog Four, and on that one, the adjustment turned out to be more lasting/stable. It’s the form factor for me, keeping this machine, as the MKII’s are bulky, and for editing sounds, I’m using Overbridge.
The degree of satisfaction (or frustration) will depend on an individual/subjective tolerance. Hope all turns out for the better in your case!
I also did the contrast adjustment procedure today. I decided it was time to open up my AK because of a key which was not triggering anymore… (Weird issue where the key was not triggering but aftertouch on that key still worked. When opening it up i noticed a connector which was simply not seated properly, so probably the thing that solved the triggering issue)
Anyways, the contrast of my LCD is much better now thanks to the brave firsts in this thread 
Just regret that I didn’t actually drill a small hole extacly over the contrast adjuster while inside, and then plug the hole from the outside with something like this…
