I noticed a slight error on the biome color key in the manual. Specifically, the actual color shown for Tropical Rain Forest doesn't match the hex code
listed, which is 20FFA0. I noticed this because I was using the image as a key to separate the biomes onto different layers to use as masks.
The hex code lists the correct color output by the program
as of the 0.19.0 release. The shown color doesn't. Every other color is correct and matches both the given hex code and the color outputted by the program.
As an added suggestion, down the line it might be worth adding an option to print black and white masks for each biome separately. For example, by using a black and white image in which only Tropical Deserts are shown, I can easily tell Blender which areas of the world map should render as a tropical desert.