Using "Install from URL" option in the Wowup client (version 2.8.0) error received:

If you look at other addons on github that install successfully, such as BigWigs (https://github.com/BigWigsMods/BigWigs/releases) they have a release.json and a proper .zip in their releases rather than just source files.

@Tyestor

I don't have the proper packing for multi-release. You can use curseforge/overwolf. I'm up to pull requests to fix wowup, but I don't have the time currently. You could install manually too.

Cheers,
Vall