I've looked for about 2 hours now and don't understand what I am doing wrong. I have installed ModtheSpire/StSlib/Basemod and I want to play Spire with friends.

When I launch ModTheSpire it says both that I need Java version 8 for it to run properly (but I have version 17 apparently and that I cant play Spire with friends because I need ModTheSpire version 3.8.3.

I can't find this version and I'm very worried that it doesn't exist.
Can anyone help with this (I can't really give an error message because I can't launch the mod).