I'll bite:
- Stained Olive Drab
- Trucks were (at the start) Raw Umber, then re-standardized as Olive Drab.
- Camo did not come out in time for the War to affectively change patterns in the field, there may have been a few, but the War ended before most factory camo jobs entered service.
-Both US and France were the same patterns/colors, there was no War in the US, so everything was 'headed' overseas to support the War effort, but obviously as things went along, support assets were being used to shuttle men, equipment and train personnel in the USA with the gear they would have (or deploy with) overseas, so some stayed back.
-Interwar changed things, but after the 20's, colors darkened (deeply), then lightened back up in the late 30's. No money to repaint or come up with schemes due to no budget and the Depression.
Sorry it took a while to answer your questions, these answers are to the best of my knowledge correct having researched a WWI Standard B for restoration and owning several WWII vehicles.
V/R W Winget
USA