Hey, yes this issue has still been happening after the update!
However there are 2 known fixes/workarounds for this issue currently.
A lot of people have mentioned removing the waterzone has been successful for them.
And for me personally, one of my good friends helped me remake my landscape with a lower resolution.
This has allowed me to edit terrain, use the brush etc.
It is still an issue, however those are 2 workarounds i am aware of.