Problem with vertical spacing and touching hairpins

I have some trouble with vertical spacing with the enclosed project (I have removed the systems that didn’t give problems). I can’t see any manual layout breaks, and I don’t understand why there’s an overlap.

There is also a problem with some touching hairpins (I have set a distance of 1 space between them in the settings, but it is not applied to all of them…).
Any help would be much appreciated!
It can be downloaded here (as it is too large to attach in the forum):!Ag6nrAwefnFvj4FBDcqm45kkEaLmRA

  1. Dorico has to make guesses as to how vertically full a system is before it casts off. It hasn’t predicted that you’re going to have music 10 ledger lines above the stave, so while it will automatically adjust the gaps between staves to make room for those ledger lines, it doesn’t have another chance to work out whether it can actually fit those two systems on one page without collisions.

  2. Typically if you insert a bunch of hairpins next to each other, Dorico groups them. If they’re grouped, they’re seen as adjacent and they’re adjusted so that there’s a gap of a space between them. If they’re not grouped, Dorico doesn’t see them as adjacent. You can always select all the hairpins on a system, right-click and go Dynamics > Group.

Thank you pianoleo!
You are right that so much ledger lines is an extreme case, but with a more standard notation some overlap still happens:

In any case, I am reporting this just in case it helps to improve the spacing. It is easy to solve manually.
I have checked that certainley, if you group the hairpìns, the the space is correctly allocated. What is curious that in the clarinet part, which has a similar thing, keeps the space between hairpins witouth grouping them… Maybe, there’s a difference between these hairpins are managed when they are in a two staff instrument, like the piano (just wondering!).