Ok the file clearly messed up the init process by being clogged with non-existing entries.
I first created/enabled/disabled/enabled several trees to see that they get added at the bottom of this file as they should. So no error there.
Instead of deleting the whole file right away I first tested to see what happened if I just deleted the bad entries from the file.
Which turned out to remedy the situation.
I manually cleaned up to just keep one line
root
because that was the only tree enabled at the moment of the modification. After that I then again created two test trees and enabled them.
After a reboot they now got initialized as expected by the creator of 66 :D
So I'll leave this here for everybody (cause when searching threads in forums, we all just scroll down, don't we?)
CAUSE
You created trees with spaces in their names which misconfigured a system file.
SOLUTION
Manually edit and delete bad entries in /var/lib/66/system/state
Only leave tree names that actually exist and are currently enabled
PREVENTION
Do not create trees with spaces in their names. This is
not a bug.
See
here why it's technically not possible for Eric to change this behavior.