LMS 8 on Synology

I tried to follow the instruction in another post on this forum but when I try to add the suggested package repository I get this error message:



I am trying to install LMS 8 on a NAS runningt Synology OS (it's a HP Micro Server with DSM 5.0-4493, running great). I have LMS 7.7.3 now and it's been running with no issues for several years now.

Hope that someone can help me with following:

1. How to install LMS 8 on my NAS? Is there another repository, the one in the screenshot is not accessible. If I choose to install the LMS 8 package manually, where can I download latest version in correct format for my nas?
2. Do I need to uninstall LMS 7.7.3 first?

Thanks in advance!!

BR

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