Hmm, maybe there is something in the game logs that could help us.
1. Turn on the failing settings again; attempt to start the game.
2. Go to your default screenshot directory -> then to the parent directory. There you should find, among other, dirs called "log" and "crashdump".
3. Check the second one first if any file is present there.
4. If not, go to the "log" dir and open the "client.log" file. Search the end of this file for something interesting (i.e., ignore all lines containing "gameserver").
5. If nothing, go up 3 times (from the log dir above). You'll find another "log" directory there. Check for any interesting lines at the end of the "tibia-launcher.log" file (again, ignore the ones about connecting to a server).
Hope it helps.