Tried your example. It didn't work too well for me.
- sharp & dblsharp don't look like the System Font
- parens are much larger than usually used for courtesy accidentals
Hmm, that would be because I used the wrong font - D'oH
Try this:
!NoteWorthyComposer(2.0)
|SongInfo|Title:""|Author:"<Name>"|Lyricist:""|Copyright1:"Copyright © 2009 <Name>"|Copyright2:"All Rights Reserved"
|PgSetup|StaffSize:20|NtnTypeface:NWC2MusikDingsSerif|Zoom:5|TitlePage:Y|JustifyVertically:Y|ExtendLastSystem:N|DurationPadding:Y|PageNumbers:0|StaffLabels:None|BarNumbers:None|StartingBar:1|AllowLayering:Y
|Font|Style:Staff Italic|Typeface:"MusikTextSerif"|Size:12|Bold:Y|Italic:Y|CharSet:2
|Font|Style:Staff Bold|Typeface:"MusikTextSerif"|Size:12|Bold:Y|Italic:N|CharSet:2
|Font|Style:Staff Lyric|Typeface:"MusikTextSerif"|Size:12|Bold:N|Italic:N|CharSet:2
|Font|Style:Page Title Text|Typeface:"MusikTextSerif"|Size:24|Bold:Y|Italic:N|CharSet:2
|Font|Style:Page Text|Typeface:"MusikTextSerif"|Size:12|Bold:N|Italic:N|CharSet:2
|Font|Style:Page Small Text|Typeface:"MusikTextSerif"|Size:8|Bold:N|Italic:N|CharSet:2
|Font|Style:User 1|Typeface:"MusikDingsSerif"|Size:14|Bold:N|Italic:N|CharSet:0
|Font|Style:User 2|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|Font|Style:User 3|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|Font|Style:User 4|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|Font|Style:User 5|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|Font|Style:User 6|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|PgMargins|Left:1.27|Top:1.27|Right:1.27|Bottom:1.27|Mirror:N
|AddStaff|Name:"Staff"|Group:"Standard"
|StaffProperties|EndingBar:Section Close|Visible:Y|BoundaryTop:12|BoundaryBottom:12|Lines:5|Style:Standard|Layer:N|Color:Default
|StaffProperties|Muted:N|Volume:127|StereoPan:64|Device:0|Channel:1
|StaffInstrument|Trans:0|DynVel:10,30,45,60,75,92,108,127
|Clef|Type:Treble
|Key|Signature:F#
|Tempo|Tempo:200|Pos:12
|TimeSig|Signature:4/4
|Note|Dur:8th|Pos:5|Opts:Stem=Down,Beam=First
|Note|Dur:8th|Pos:4|Opts:Stem=Down,Beam=End
|Note|Dur:8th|Pos:n4|Opts:Stem=Down,Beam=First
|Note|Dur:8th|Pos:3|Opts:Stem=Down,Beam=End
|Note|Dur:8th|Pos:b3|Opts:Stem=Down,Beam=First
|Note|Dur:8th|Pos:2|Opts:Stem=Down,Beam=End
|Note|Dur:8th|Pos:b2|Opts:Stem=Down,Beam=First
|Note|Dur:8th|Pos:1|Opts:Stem=Down,Beam=End
|Bar
|Note|Dur:8th|Pos:0|Opts:Stem=Down,Beam=First
|Note|Dur:8th|Pos:b0|Opts:Stem=Down,Beam=End
|Note|Dur:8th|Pos:-1|Opts:Stem=Up,Beam=First
|Note|Dur:8th|Pos:b-1|Opts:Stem=Up,Beam=End
|Note|Dur:8th|Pos:-2|Opts:Stem=Up,Beam=First
|Note|Dur:8th|Pos:-3|Opts:Stem=Up,Beam=End
|Note|Dur:8th|Pos:n-3|Opts:Stem=Up,Beam=First
|Note|Dur:8th|Pos:-4|Opts:Stem=Up,Beam=End
|Bar
|Text|Text:"²"|Font:User1|Pos:-3|Wide:Y|Justify:Right
|Note|Dur:4th|Pos:-3
|Note|Dur:8th|Pos:-3|Opts:Stem=Up,Beam=First
|Note|Dur:8th|Pos:-3|Opts:Stem=Up,Beam=End
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-3
|Bar
|Note|Dur:8th|Pos:-3
|Rest|Dur:8th
|Note|Dur:8th|Pos:-3
|Rest|Dur:8th
|Rest|Dur:Half
|Bar
|Note|Dur:4th|Pos:4
|Note|Dur:8th|Pos:4|Opts:Stem=Down,Beam=First
|Note|Dur:8th|Pos:4|Opts:Stem=Down,Beam=End
|Note|Dur:4th|Pos:4
|Note|Dur:4th|Pos:4
|Bar
|Note|Dur:8th|Pos:4
|Rest|Dur:8th
|Note|Dur:8th|Pos:4
|Rest|Dur:8th
|Rest|Dur:Half
|Bar
|Text|Text:"²"|Font:User1|Pos:-3|Wide:Y|Justify:Right
|Note|Dur:8th|Pos:-3
|Text|Text:"´"|Font:User1|Pos:-3|Wide:Y|Justify:Right
|Note|Dur:8th|Pos:-3
|Text|Text:"¹"|Font:User1|Pos:-3|Wide:Y|Justify:Right
|Note|Dur:8th|Pos:-3
|Text|Text:"³"|Font:User1|Pos:-3|Wide:Y|Justify:Right
|Note|Dur:8th|Pos:-3
|Text|Text:"×"|Font:User1|Pos:-3|Wide:Y|Justify:Right
|Note|Dur:8th|Pos:-3
!NoteWorthyComposer-End
Also, IMO, User fonts designed to supplement the System Font need to be sized so that they are:
- 1/2 of Staff Metrics
- equal to Staff Metrics
- 2x, 3, or 4x Staff Metrics
Your example uses 20pt Staff Metrics and 14pt User1.
If you change to a more standard 16 or 18pt (or a 12pt study score), what change do you make to User1?
I don't use parens around accidentals. Takes up too much horizontal space.
Someday, we will be able to use nwctxt in Edit->Paste as New File 
As for the size, perhaps I could have been more careful when I set this up. I no longer recall what criteria I used to for these glyphs as I usually expect to see the *Dings fonts at 100% of staff metrics. It may well be that like my Coda and Segno glyphs (I like some things to be quite large so they aren't easy to miss when sight reading and one hasn't really had much time to study the score) I wanted them to be very visible...