My characters aren't appearing in the Hall of Fame. How do I fix this?

Dying.
You'll score the first time you die, so the longer you survive from the beginning, the higher the score.

This is completely wrong. The actual answer is that the game does not record scores unless you are running GoG Galaxy when you score. If your character dies while Galaxy isn't running, no record is created and that character will never score.

On the other hand, if you are running Galaxy, your living score-eligible characters do show up in the hall of fame.

I don´t really know,

But I think is because if you don´t have galaxy run in yor PC the data doesn´t can go ahead to thing trunk.

It´s the same with multiplayer games, without GOG Galaxy you can play with your friends because GOG Galaxy is the "server"

Sorry for my bad english, I hope you can understand everything.

Good game ^^