Hey! Still puzzled by this one, and the error seems to be thrown by a different site. I assume it probably is something about permissions, but I honestly have no clue what exactly it could be.
One more thing I thought of: It is possible that the error appears in a normal log message that starts with "Error in main game loop:". Maybe you can find that. Otherwise, I'll have to see if I can find some way to reproduce the bug myself.