I can confirm that the rename worked for me in getting separate distribution downloads for 7 and 8 on food4rhino.
Xray | Food4Rhino
Also, Steve B said that a YAK package is only a renamed zip file (as of June 2023, thread link below). I just tested that statement again by renaming one back (YAK->ZIP) and opening it in windows explorer, so it looks like there’s no hidden data inside which Rhino looks at, only the manifest file and whatever other files you include.
Help using Package Manager to distribute a plug-in built with C# - Rhino Developer - McNeel Forum
I haven’t tested Rhino version number checking on actual installs to confirm that Rhino blocks the attempt if the version isn’t right, but I started this thread because it apparently wasn’t checking Win/Mac to see whether it should try to install.
Wow, now that’s a bit of automation and testing.