\once \override Accidental #'stencil = #ly:text-interface::print
\once \override Accidental #'text = \markup{ \override #'(word- space .
0.4) \line {\semiflat \flat }}
OK. There isn't a way to write into the setup once and for all, "the
3/4-flat accidental is ..." ?
Same mod, just leave out the \once... =)
Again, you might want to add this in to the context definition
itself, e.g.,
\layout
{
\context
{
\Score
\override Beam #'damping = 100000
\override Accidental #'stencil = #ly:text-interface::print
\override Accidental #'text = \markup{ \override #'(word-space
0.4) \line {\semiflat \flat }}
}
}