Actually, from that DVD they even go further and say the roundel is a white propellor against the blue bavarian sky. Kind of cool.
About BMW building engines that killed the allies, hmmmm....
We're all humans, and we all fight. Regardless of what side is right, why is it so strange if a company makes useful products to support that country's war effort?
My avatar, Bethlehem Steel, built the Golden Gate Bridge, Rockefeller Center, and Madison Square Garden. But they also built tanks, munitions, and ships during World War II.