Low C Horn, Contrabass Trombone

Just to check that I'm not crazy, working on Wagner, and the .xml on these seem wildly wrong? Low C horn is a transposing instrument, down an octave from middle C, but the .xml doesn't reflect that. Worse, since I have to change instruments to change transpositions, I can't fix it except via editing the .xml and handing it over to github.

Contrabass trombone's range is wrong, too, I got a bright red 'not in range' indicator when transcribing a Wagner part, and between MS and Wagner... I trust the guy who is the reason the instrument exists. So I did some research. There are two kinds of Contrabass trombone, BBb and F. F is the standard one, and MS does not differentiate. From position charts I found, F Contrabass goes from F1 to F4 nominally, and F0 to F4 in reality. So C4 should really be easily in range. 29-65, and 17-65.

If you want to live dangerously, The top note of a BBb Contrabass is Bb3, and the lowest is C0, so the amateur range should be from F1 to Bb3, 29 - 58, and the pro range from C0 to F4, so... 12 - 65.

Oh, and C horn isn't in F clef. That was weird. Someone tell me if I'm wrong? The chart is slightly confusing, it's written for Horn in F players transposing other parts. If the C is below the usual hor in F, it transposes an octave down. Also, the Wagner part backs that up - the part would make much more sense an octave down from what MS is currently playing it at.