I finally succeeded to use my graphic symbol, thanks Daniel!
then I found a new problem, it seems that vertical lines do not display in the percussion kit 5 lines staff, while it displays correctly in the same project on ordinary singer / instrument staves. The horizontal line feature works …
cann’t attach project file even one bar size 2.95Mb!
+1 vote to add the ability to create vertical lines on percussion kits. The common use case is annotating specific drum/percussion parts that are not part of standard notation. This is common in musical theater drum parts, which often include a lot of percussion instruments assigned to the drum kit player (see example below).
Seems like the only way to get this to work is to make both end-points attached to a rhythmic position, then make manual Engraving adjustments in the score and parts to get it to line up correctly? If I make either end note-attached then Dorico seems to refuse to create the line. Is that your understanding as well?