The "DORA" was a variant of the FW190 ...FW190 D...or "Dora" (long nose). It was I think built first for high altitude intereception and was later moved to a homeland defensive fighter. The red bottoms of JV-44 were used to keep the german ack from shooting down their own fighters. They were often tasked with support roles for the 262 as Robert shows. As they glided in for landing those pesky Ponies would try to take them out..as it was really the only time one could catch up to a 262.
Lol..you might already know all that but I think the "Dora" name was sort of like how the bf109G was the called " Gustav" I reckon. Perhaps the reference you read uses the term to describe a elongated nose on the Stuka. I dont have any Stuka stuff....