Hi, @fercho I have some news for this
My PR has been accepted, so new options are available (nighty builds only)
overlay0_auto_x_separation = true
overlay0_auto_y_separation = false
Which are exclusively for auto-scale mode. “True” means separation (shift to sides) is enabled.
Previous parameter now works only for manual adjustment - overlay0_block_x_separation = true
means separation is blocked.
You may try to use it even it is not in stable version. Also notice that default value for Y axis is “false”, so if this parameter is not present in config overlay will be centered vertically in portrait and landscape modes