Unity 4.2.1f4, manual activation fails

I installed Unity 4.2.1f4 and Unity Hub:

1. I had installed them in a directory where names had accentuated letters (é). When I tried to add the two Unity that are already installed in the same directory, Unity Hub didn't recognised them, saying that the executables were not signed by Unity Technologies. Both are of course, I downloaded them here. The error message was wrong, the problem came from that accentuated letter in the directory's name. I modified that and Unity Hub eventually accepted my installs.
2. When I try to create a project in Unity 4.2.1f4 I get this message: "SSl peer certificate or SSH remote key was not OK".
3. I tried manual activation but it doesn't work. I saved the license request file, went to this page (https://license.unity3d.com/manual), loaded it and clicked on "Next", all what happens is that the plage flickers and get back to the "sign in" step.

Could you please fix this problem? Thank you.

 

I just found out why manual activation wasn't working and it was a really stupid little thing. I appears that, when I saved the license request file, it's name contained dots. I removed the dots and manual activation worked.

I hope my experience will help others!

Oh crap, I sent a bug report...

 

It was too good to be true. After downloading the license, launching Unity, clicking on load license everything seemed to be fined but Unity crashes instantly when I try opening it.

 

As far as I understand it, the Hub doesn't play well with old Unity versions. So I'd avoid it when using pre-2017 Unity installs.

I also get the license prompt whenever I switch between 5.6 and 2018.1. It's irritating, but there it is...

 

The problem with the hub not recognising installs if they are made in a directory containing names that have accentuated letters is something else entirely; I shouldn't have brought it here.

I'm trying again and installing Unity 4.2.1f4. I'd really like to make it work. Last time.

 

Okay, tried again installation and activation worked but when I launch Unity 4.2.1f4 it just crashes. That's it.