Thank you for your report.
I don't own Photoshop so I couldn't confirm it.
I don't know the cause and countermeasures, so I would like to prepare data with few layers.
If you can confirm it, I would appreciate it if you could report it.
春菊天うどん
2020-11-01 10:54:45 +0000 UTC
maybe some brush from csp can't work on photoshop....so it's look like missing a layer.
alk
2020-11-01 10:53:28 +0000 UTC
Have layer missing when opening with photoshop cs6,but no problem with clip studio paint