What you can try is to do a manual installation (remove the autoyast=...) parameter and try to add the add-on manually then. If that fails too, then there is something wrong with the add-on. If you can add it manually, then there is something wrong on the autoyast side.
I performed the manual installation like you had suggested. During the manual installation, I did not see the error and I was able to install the 3rd Party RPMs that I had included.
If it's an autoyast issue, you can try to move the add-on from DVD to a USB stick, just for testing, and use usb://.... then for the add-on URL. So we know if it's an issue with the cd:/// url
I copied the contents of cd:///updates to a usb so that it would be located at usb:///updates. I altered the add_on_products.xml file so that the URL specified was "usb:///updates" instead of "relurl:///updates". I then attempted an automated installation using my existing autoinstall.xml file, I received a message similar to what I had originally seen--it said "Unable to add product usb:///updates". -Jason This transmission may contain information that is privileged, confidential, and/or exempt from disclosure under applicable law. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution, or use of the information contained herein (including any reliance thereon) is STRICTLY PROHIBITED. If you received this transmission in error, please immediately contact the sender and destroy the material in its entirety, whether in electronic or hard copy format. -- To unsubscribe, e-mail: opensuse-autoinstall+unsubscribe@opensuse.org For additional commands, e-mail: opensuse-autoinstall+help@opensuse.org