Chord Symbol Fonts
When I change the chord symbol font (Format - Style - Text Styles - Chord Symbol) the accidentals in the chord name do not appear in the new chosen font: 
In (Format - Style - Chord Symbols - Appearance) the "Standard" button is chosen.
Please advise. Thank you for your time.
Comments
Sample score needed. My guess is you enter the chord symbols wrongly, using a flat sign rather than a a plain b (which MuseScore then turns into a proper flat, matching the font)?
What font did you pick? And why not Format - Style - Chord Symbols - Appearance > Jazz?
Your font needs to have a glyph in the official Unicode / SMuFL codepoints. My guess is that this is the Jazz font designed for Finale, which I don't think it is fully compliant. So the flat sign is being substituted from another font. You should be able to create a customized chord description file to tell MuseScore where to find the flat sign.
In reply to Your font needs to have a… by Marc Sabatella
Thank you for your comment - you are indeed correct. I'm trying to use the Jazz fonts from Finale, the only accurate rendering of the Real Book look that I know of. I know very little of font rendering programming. I did find a font description file on GitHub (https://github.com/musescore/MuseScore/blob/master/share/styles/jazzcho…) in which I changed the font family name from "MuseJazz" to "Jazz" which produced some interesting results when loaded, but nothing actually useful to a musician. If you have any information on how one creates such a customized chord description file, I would be grateful. Thank you once again for your time.
In reply to Thank you for your comment -… by ExpatMusic
Your best bet is to look at the XML files that come with MuseScore, in the Styles folder under wherever you installed MuseScore, read the comments, and start laying around. I'm not sure it's really worth the effort, but keep us posted!