Can't install a working Papyrus

I'm trying to install Papyrus, I've tried on and off the last 2 years, and the best I can get is an instance that gives an error popup window several times before failing completely. Anyway, I don't care what version, how it's installed, I want someone to tell the the correct, official or normal way to install this thing. I just need it to work in the most simplest, generic manner, nothing fancy.

I'm using Ubuntu, I've got JavaJDK installed. I've tried the Eclipse-installer and then using Papyrus official update, this results in Papyrus not even appearing in the IDE. I've tried installing Papyrus-classic, this works with the error popup being displayed repeatedly until it fails completely.

What's the official correct way to install this thing? I will try the recommended method from scratch and report what happens - this is ridiculous, how can it not be possible to simply install this thing?