Creating Battle Royale Sized Islands Feedback

This is the first issue I encountered. Would love to make large islands with a single ocean actor: https://forums.unrealengine.com/t/normal-uefn-ocean-actor-cannot-create-large-islands/647055

Then after I started painting, I encountered this which didn’t happen on other islands

I made some layer info on the mud and then noticed that past the landscape chunk I was working in it didn’t remove the grass blades (EDIT: Restarting UEFN fixed):

Seems only one chunk is not affected:

Pressing to sync with Creative and immediately closing the project crashes UEFN:

After launching Creative, I also got this on the terrain: