I have read your post in its entirety, and what you are trying to do by loading an image then changing a key is not going to work well if at all. I and others who have responeded to your post do understand your question and what you are trying to do.
The Key Change utility was not designed to be part of the imaging process.
I will go thru the steps so you will understand. I know that this is not the answer to your direct question does the key tool work with sp2c. That answer is yes it works like it is supposed to. The problem in your case is that you are not using the tool for what it was intended. You don't use a hammer to put a screw in a wall. Sure the screw will go in but you will not have a satisfactory result.
Here are the steps for imaging.
Do a full installation on your first PC.
Configure this PC the way you want it.
Make a folder called Sysprep on the root drive. (Usually C:\)
Copy the contents of the tools\deploy.cab file from the instalation CD into the Sysprep folder you made.
Remove the CD from the drive.
Open the Sysprep folder on the root drive.
Run the Sysprep.exe utility.
Select the option to reseal.
Answer any prompts to overwrite user and system id's with "yes"
The utility will then run and turn itself off.
Make an image of the drive you just created.
Restore the image you just made to another drive.
You can now use the two drives on the two machines.
Whan you boot them up they will ask you for the new info.
You can use your original product key on the machine you made the image from and your second key on the second machine.
You can also use this image on any other identical hardware as long as you have the product keys to support it.
This is the most basic solution that I have given to you. It is also the fastest for low volume duplication on identical hardware.
