At that point, the observer was kicked out by the other two players from the game due to constantly having connection issues, which rendered the match unplayable.
This crashed when trying to read the color scheme for country "UnitedStates" from an ini file. The current color scheme index was -1 and thus accessing the list of color schemes to get the name of the current scheme crashed.
I don't know what set the index to -1. YR uses 0 as default.
The last thing I did related to colors was the LoadScreenText.Color fix. I don't think they are related.
Is this crash reproducable / did it happen ever since?
At that point, the observer was kicked out by the other two players from the game due to constantly having connection issues, which rendered the match unplayable.