Yes I have seen alert you mention. Is there solution to thes problem? I have firewall and so forth off as I write before. If no solution: REFUND of money paid then. Scenrey is half ass not full. Why pay and have no satifaction.
Stop, calm down, and don't be too quick...
1) The scenery and the activation WORKS, otherwise lots of people wouldn't be able to use it...
2) Which means, something is not right or unusual on your system.
3) We WILL find it out what is it, and you WILL have it working
Now, let's start from scratch...
What OS are you using ?
Are you using some flight sim addon that "steals" the main FSX window focus ? Like atc program, atc chat windows, or anything like that ?
It might be the registration dialog IS there, but (because of another addon interfering) it's simply *behind* the main FSX so, you only see a black screen. Try if it comes out with ALT+TAB, or if you see its icon in the Taskbar.