Just wondering, whether this behaviour is expected: according to MAME/MAWS ddrja seems to consist of only the nodump (gc845ja.u1) and CHD 845jab02.chd. With "hide missing" checked , the set is still marked as missing. My guess is, that this is because there exists no zip archive ddrja.zip for this set in this case, correct?
I seem to remember that this had happened once before for another set and you had answered this already then. But I could not find the thread now, so I maybe wrong.