Hello Gregory

Color constans are working fine now!

Transparent is not working. May be this is another problem and has nothing to do with the constants.

Help says:
you may have for each bar a different color. In this case you must set Transparent as Color property. Additionally you can define for each bar an individual color with ColorArray, ColorString or SetColorValue.

Example: ChartX1.AddRegion
ChartX1.Region(1).AddBarSeries
' If you have single bars and want to have different colors for each bar:
ChartX1.Region(1).BarSeries(1).Color = Transparent
ChartX1.Region(1).BarSeries(1).Colorstring = "Blue*Green*Black"

But when setting color first to transparent and then using colorstring to define some colors,
all bars are transparent (just the boarders) ??

Nevertheless: Thank you very much.

Best regards
Albert
P.S. I also wanted to mark your answer as solution, as i did with Sergeys answer, but the checkbox was not offered. ???
Sorry