From one of my apps, what worked for Google Charts colors is:
["green","red"] or ["FF9900","3366CC","DC3912"]
So I had to use double quotes instead of single quotes.
For rounding numbers, I did that in the microflow datasource for each chart.
If you want to find detailed configuration examples, you can find those on this site: https://developers.google.com/chart/interactive/docs/
Choose a chart type in the menu on the left side of the page, then click Configuration Options in the menu on the right side of the page for chart type you selected.
Hope that helps,
I realized getting these right took some trial and error for me, so I thought maybe a few examples could be helpful:
Settings for this chart are: