Yes, they must have changed the compression format after version 9.
It sounds like what your trying to do is have a full backup of the XP system on your new system so you could later get into it if you ever needed anything.
I can think of a few options.
1) Make or convert the most recent backup into an uncompressed image as you have done and keep it on the new system. The downside I see in that is that it's going to be much bigger, and like me, you may not be able to get version 15 to list it as a backup. Like I said I can open the images but even when putting it into the backup folder I still couldn't get Ghost to add it to the list of backups. Also, who knows what changes future versions of Ghost may bring and we still don't know if version 15 could do an actual restore with it. (Don't loose your version 9 disk)
2) The perfect and easiest solution would be to make a Ghost 15 backup of the old system before retiring it.
However, I don't know the legalities involved, so please do not take my advice without checking with Symantec.
The easiest way would be to use the restore disk to do a cold version 15 image of the old system but if you were allowed to do that is another matter entirely. Maybe since this whole problem is due to the fact that the older version isn't fully supported it might be allowed.
Otherwise you may have to completely uninstall it from your new system, install it onto your old system, do the image, uninstall it and re-install it onto the new system.
That would be my very last resort, I hate making so many changes to systems without any other option and I hope that you wouldn't be forced to do that in order to comply with the license you may also run into problems if for any reason you wanted to install version 9 back onto the old drive before storing it.
Another option would be to remove the old drive and temporarily install it in your new system to image it.
That would comply with the license since you only have Ghost installed on one system, but you would have to be very carefull that the drive was not only installed right but that the 2 drives never "see" each other. You could never let the system boot into windows or one of the drives will get re-lettered and will not easily boot again.
(check all the problems in the forum about that).
The last option would be to use something else, maybe you have an old DOS version of Ghost or another tool.
It's nice having "everything" because it seems like no matter how hard you try you always forget something.
But maybe you could just zip or backup all the folders you need to keep.
Best of luck Archie,
Dave