Customized report colors "snapping" to windows default colors - vba

Question

I have a chart in an Access 2010 report for which I am trying to set colors of different series dynamically. The user can use checkboxes to select series to chart, with the intent being that the series on the chart will take its color from the BackColor property of the checkbox's label.
The problem is that when I run my code to create the report, the colors used are not the ones on the corresponding labels. Instead it looks like they are "snapping" to the list of colors at the following link, referred to as "standard windows colours". List of standard windows colors in RGB and Long
For example:
With myChart.SeriesCollection(1)
.Interior.Color = RGB(195, 215, 155)
End With
Sets series 1 to a dark grey color, and debug.print myChart.SeriesCollection(1).Interior.Color returns 12632256, rather than 10213315 like it should. (Long color = Red + Green*256 + Blue*65536)
I have tried opening the chart object and defining the custom colors that I want to see on the palette for the chart, and setting the appropriate colors for the series manually. This works until I try to programatically change anything, at which point, all of the colors snap to the list I linked above.
Any ideas for how to dynamically set chart colors to custom values?

Answer 1

Managed to answer my own question. Manually customizing the palette in MS Graph was necessary, but from there, I need to reference the colors by their index on the palette (using .Interior.ColorIndex), rather than from their RGB or Long code. The index numbers for the palette are not in any logical order, but can be found in a file accessible from this site.
It's not quite as dynamic as I had hoped for, but this is definitely good enough for what I need to do.