Hi,
I have exactly the same problem, and also have all the above mentioned registries and stuff!
It's a virus that removed many parts of the registry on my computer. I was able to recover all of them and restart the services, except for the ActionCenter icon, which does not load, and is greyed out, so cannot be turned on!
Any other suggestions as to what make this icon work in the taskbar?
Even I had the same problem. Can you explain how to fixed all the other issues?