Mosaic 1.5 has intelligent note-spelling algorithms, which it employs when recording MIDI data and importing standard MIDI files. It knows that chromatic runs should have sharps going up and flats heading down. But Mosaic's algorithms go even deeper. They take into account factors such as key signature, mode (major or minor) and the complex details of voice leading. For example, take a look at the second beat of measure 2 below. Notice how Mosaic chose an augmented interval to make the voice leading come out right from the diminished 7th into the D minor chord. Mosaic will save you loads of time by getting it right most of the time. If you prefer different spellings, you can always adjust them manually.