Janis, do not feel bad about your choice of WD-40. It is the right product for trying to unstick your mechanism since it cleans and lubricates. Once you loosen up the lift you can wipe the threads as dry as possible and switch to a dry lube product.
I sold my Delta router/shaper a while ago so this is from memory. Remove the round fill plate and check carefully with a small mirror to be sure nothing has fallen in and is blocking the motion. (always use the vacuum hose to prevent build up in the cabinet)
Are your adjustment threads rusty? If so spray them with PB Blaster to remove the rust. Most often it is simply a build up of sawdust in the threads, and an air hose is the easiest way to remove that. What area do you live in? This is how we direct you to assistance when needed.
"Living in the D" (this means Detroit!)
"It's fine to disagree with other members as long as you respect their opinions"