Colurs need to be in HEX format e.g. C1C1C1. A tables of colours and there HEX code can be found here

{{infotable
|Maintitle = 
|Maintitlebackcolour = 
|Mainwidth =
|Body =
|subheading1colour =
|subheading1 =
|subheading1width =
|subheading1text =
|subheading2colour =
|subheading2 =
|subheading2width =
|subheading2text =
|subheading3colour =
|subheading3 =
|subheading3width =
|subheading3text =
|subheading4colour =
|subheading4 =
|subheading4width =
|subheading4text =
}}