Now I am probably not as thin as originally installed as there are some things that you just try and work with.
Modelio has a few issues that you need to resolve to get it working.
Firstly download the software, mine was the open source version 3.3
Unpack it and move it to a directory.
Then you need to make sure your Java is correct. Modelio 3.3 requires java 8 you will need to make sure it is your default Java version, there are a few notes around on Ubuntu you require the alternatives command sudo update-alternatives --config java
I have then set the -vm parameter in modelio.ini to your Java 8 location