Bitonal chords (eg. G# plus Gb)
There's NO way to notate bitonal chords (eg. G# and Gb simultaneously). When you try, you get a mess of note heads.
That's a continuation of http://musescore.org/en/node/8119
Here I put some examples of Musescore and how they should look (the picture may appear cut, in that case click it).
Notice that there are 2 kinds of bitonal 'cash':
1) only 2 notes, one with an accidental and the other with another accidental (see the Standard Music Notation Practice)--> the notes are arranged in a Y shaped stem.
2) chord with many notes plus one bitonal 'crash'--> the chord is arranged in a normal vertical stem and the 'added' note is put in an auxiliary diagonal stem (see Scriabin example).