Hi Paul,
Good work, as usual! I like how I can click on the SN -> DN link at the bottom of your web pages and see (for example) the new quarter-tone accidentals in DN, not just in SN. I'm still partial to DN, but I can't claim substantial experience with either of those two Clairnote variants.
Supporting quarter-tones is a sensible and important first step. There are some microtonal enthusiasts who shudder at 24-ET (the division of the octave into 24 equal parts), because they are devoted to other microtonal scales such as ones using just intonation. But quarter-tone (and three-quarter-tone) sharps and flats are the most common accidental signs in general use, so they're a logical first foray into microtonal notation.
Best,
Doug