Recognizing M and m in chord names

Me too.

The "chord name magic" (good term :-) recognizes chords according the currently selected chord name style. See Chord name in the Handbook. Different chord name styles recognize different abbreviations.

There is no style that currently recognizes m and M. You'd have to customize one to do that. The "cchords" style are designed for easy customizability, so I'd recommend using one of those.

But really, I would recommnend *not* doing this in the first place :-). There are few things I hate worse as a player than charts that make me guess by looking at a chord with only a single letter whether it's a capital M in a smaller font or a lower case m in a larger font. At least if one uses "m" and "maj", as the default style does, I can tell because anything without "aj" is minor. Similarly if you use "M" and "min" - anything without "in" in such a chart must be minor. Virtually no respected publisher uses "m" and "M" for this reason. Something to consider.

FWIW, in 2.0, none of this business of selecting or customizing a chord name style to tell MuseScore how you want to type your chords will be necessary. You will be able to type whatever you want (within reason) and MuseScore will recognize it - no fiddling with chord name style files. See http://musescore.org/en/node/21202.

For the time being ...
MuseScore has several different chord styles available. The default one (stdchords.xml) *should* allow you to type 'F#m' and have the chord name magic recognize it and change the '#' to a sharp sign.

Also, jazzchords, along with stdchords, recognizes the 'm', but not the 'M', so entering a major chord simply requires entering the name of the chord's root. That is, typing a 'C' displays a C chord - without an 'M' (or 'maj') suffix.

You can change the chord description file in MuseScore under menu item: Style / Edit General Style / Chordnames then hit the browse button and select a chord style.

Here's a neat way to view the various chord files:
Go to menu item: Plugins / Lead Sheet / Create Chord Chart where you can open each chord name file to see how it 'displays' the various chord names. Some styles 'display' triangles, slashed circles, etc. To discover how to actually 'spell' the chord name, simply double click on any chord name and the correct computer keyboard characters will appear. These characters are what you enter so the chord name magic recognizes it. (Gotta love that - *chord name magic*)
You may find one of those chord description files more in sync to your preferences for naming chords.

Regards.