Hi,
Is it possibile to use roman numerals in rehearsal marks? I can’t find this option nor in the Engraving options, nor in the properties.
Paolo
No, I don’t think there is such an option.
You’ll have to fake it by changing the index for Alphabet marks, plus prefix or suffix, or use System Text.
I was actually looking at a score that had Roman numerals for Rehearsal Marks yesterday, thinking “Well, that’s the first thing I’m changing!” 
Ben, it’s the same for me. Never seen one before. Maybe we were both caught in a new trend!
Paolo
Any update on this?
No, Dorico doesn’t have a way to use Roman numerals for rehearsal marks. It’s quite an unusual requirement, and isn’t often requested.
The planets uses it, and I’m trying to recreate it as closely as possible in Dorico…
Why, I wonder? It’s hard to imagine improving on the existing edition of The Planets.
When I say recreate, I mean copy it in exactly, not compose my own version of it.
Anyway, the original planets, on imslp anyway, uses Roman numerals. And as I tried to enter Roman numerals at a rehearsal mark, I found I was unable to. Hence the question/comment on this thread.
It is really very easy to fake. Set RM to letters. For RMs I,II,III,IV,IX set the index to 9. For RMs V,VI,VII,VII set the index to 22. And for RMs X,XI,XII,XIII, XIV, XV, XVI, XVII set the index to 24. Add the appropriate suffix to each.