Reinstalling CS4 Photoshop Extended rejects valid original serial number

I am Reinstalling PShop CS4 Extended to a new computer (old one died).  Have box with orig. serial number, but it is rejected during 1st run after installation ran OK.  Adobe-CHAT confirmed it was a valid SN for PShop Extended, but they can't help with "Extended". Said I should post to Forums. 

Searching, found another forum thread that says: 

"As I understand it, there's one download for CS4 Standalone.

"Download Adobe Creative Suite 4 (CS4) products

"The serial number you enter will determine whether the CS4 Standard or CS4 Extended feature set is unlocked."

Q1:  If this is true, seems I should be fine installing from the CD with SN.  But it doesn't work.  Any ideas?

Q2:  I CAN install/run a 30d trial copy, and it says I can validate it later.  HOW do I upgrade a trial copy given a good SN?

Q3:  Other ideas?  I've tried a lot of angles for nothing.  Thanks!