Setting right color in Format pane for a Power BI Custom Visual in R html

Hi! I am working on a Power BI Custom Visual using R. The component is generated from the command 

pbiviz new rVisualSample -t rhtml 

and the code is extended using Visual code editor. It should be familar to many I guess. My problem is not the visual itself, but added functionality to change the color of a line chart. It is using straight forward code in capabilities.json, settings.ts and script.R to manage what you see below. The strange behavior is that when I pick one of the standard color themes, the color differs from the hex color in power and what the R script is getting (from Power BI). But if I try selecting a custom color from the color spectre it works correctly. Look closely at the pictures below, you will see what I am talking about. Has any of you experienced this bad behavior and has anybody an explaination what is happening and perhaps a solution to solve this issue? please let me know

Regards Geir

I am sorry that not everything in the picture is in English here, but I guess you are familiar with the Power BI Desktop tool