How to install RHI file on Rhino 6?

Hi - this probably a very stupid question, but I want to give the new Bella renderer a try… but I completely failed at the very first step: How to install it?
I had Rhino 7 WIP installed and when I doubleclicked the RHI file it installed beautifully in Rhino 7… where it does not work because it only runs with Rhino 6.
So I deinstalled Rhino 7 WIP and tried again - but it seems Rhino 6 does not know the RHI file. Then I read something about rhiexec.exe - but that is not installed on my machine.
I even tried RhiFix.exe - but with no luck (…Detecting Rhino Installer Engine Executable … not found.)
Can someone please tell me what I am doing wrong? It’s getting a bit frustrating.

Idk, maybe drag the RHI file onto rhino?

No, does not work. I then get an error message saying something like “… no assiciated app found to run this file - please install the necessary app…” The error message is in German - so I have no 1:1 english text.

Found the problem:

Rhino 7 WIP seems to OVERWRITE the Rhino 6 rhiexec.exe with the Rhino 7 version. That’s why it installed the RHI on Rhino 7 when I double clicked it. But then I uninstalled Rhino 7 and it also uninstalled the rhiexec.exe - since it was part of the Rhino 7 installation. On my still installed Rhino 6 there was no rhiexec.exe anymore. Therefore, the rhi had no associated app.

So I did a complete re-install of Rhino 6 and now it works. I could successfully install Bella Renderer with its RHI file. To me this behaviour (Rhino 7 rhiexec.exe overwriting the Rhino 6 rhiexec.exe) is kind of a bug and should be avoided.


@brian This may be worthy of your attention, or at least comment: