Thanks very much.
That did it, with a bit of messing about. I’d tried that earlier on, but had gotten syntax errors and assumed they had to do with putting the ties in the chords, but it must have been something else.
I figured it would be no problem to fix this by tweaking the shape of ties, like so: <cis! e>1-\shape #'((0 . 0.5) (0 . 2) (0 . 2) (0 . 0))~ | <cis! e>1-\shape #'((0 . 0.5) (0 . 2) (0 . 2) (0 . 0))~ \< | I’m pretty sure that you can solve this by putting the ties on the individual notes inside the chords, rather than on the chord. I would have tested it to demonstrate if you had provided a tiny example. http://lilypond.org/tiny-examples.html