Activation is done with your Stardock.net account email id. You really need to contact support@stardock.com to get useful assistance in getting these products activated. They need to see what's happening with your account on Stardock's servers. I've given you as much information as I possibly can.
Would you mind clearly stating what should work to register IconDeveloper and SkinStudio 6 Pro? I need to point out that I have a different email address for my Impulse/Stardock.net account registration than I have for my Object Desktop Ultimate
If you are using the OD Ultimate Serial number you found in your Impulse Registrations with your current email id for Stardock.net to register IconDeveloper SKS Pro then that is correct
Step 1). Verify you have the correct Object Desktop Serial Number in Impulse Registrations. Click on the Key icon found on upper right of Impulse.
Step 2). Verify you are using the Stardock.net email id. Click on edit Stardock.net account Button found on the Impulse Registrations screen you opened in step 1).
Step 3). Start IconDeveloper the activation window will pop up.
Step 4) Input your Stardock.net email id
Step 5) Input your Object Desktop Serial Number you found in Impulse Registrations in Step 1).
If this doesn't work contact support@stardock.com and explain the situation in your email. Reference this thread.