I got the server to start up, with most of the previous configurations. I miss all the plugins, some app is broken and probably something else (I'm still checking it out), but at least I lost no data.
I tried to install a different version, not the latest, and it worked. I think I never upgraded to 6.12.x and so by copying the config from 6.11.x to a new install of 6.12.x it was breaking something