I got same result if to set this propety by programmatically:
after
ChartControl.BackColor = Color.FromArgb( 160, 220, 160 );
drawing tool Text (F12) work properly,
and after
ChartControl.BackColor = Color.FromArgb( 50, 160, 220, 160 );
drawing tool Text (F12) work very strange and not properly.
If this is bug - please fix it please.
In attachment - indicator that illustrate problem.
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