I just figured out why you can't get it to work, Stashu.
You're turning it the wrong direction.
The lowest setting is farthest from off. You want to turn the knob at least halfway in that direction, then on the way back to off, where the knob gets real stiff before it boings off, that's where the delicate high settings are.
You and I have put so many words into this that I have to go make a video for ya, even though I know you'll understand exactly what I mean.
It's something everybody will need to understand and a little video will make it real obvious.
One other thing...
You can use those plastic zip-strap anchors and zip-ties to hold your wiring running down the back and get rid of the black tape holding your wires down.
That's actually what they're for. Assuming you have some more?