When i look in the addon manager there are lighter letters around the product active and serial lines.(addon manager-cloud9-amsterdam-product active.)
Does his mean that the serial number is not inserted??
Exactly the opposite: if the options to register the serial number is disabled, it's because the serial has been already activated successfully so, there's no need to have that option available again.
I,m running also Norton software as the security software.
That's not an antivirus problem. If you had an antivirus problem, the Addon Manager wouldn't run. Since you are seeing its menu, it means it's running correctly.
So, your problem doesn't have anything to do with registration or activation, and must be something else. Check the scenery shows in the Scenery Library. If not, just add it manually.