This means the VFX Graph for water splashes broke because it was imported without URP being installed. As a result, the particle rendering output node in the graph disappeared.

Solution: re-import the package from the asset store

Solution: Change the spawning criteria so fewer emitters are created. Such as increasing distances, or using multiple components for a different sections of the river.

Solution: Update to a more recent version of MicroVerse (v1.7.2+)

This is a limitation of the method in which the topology is generated.

Increasing the “Turn Filter” value under the “Triangulation” tab can mitigate this

Unity saves procedural geometry with the scene file, as each of them are unique. Outside of the scene it was created in (such as in a prefab), the data will be gone.

Solution: Export the river as an FBX mesh, and use that in the prefab instead

The demo scene was constructed using Universal Render Pipeline materials, which your project isn’t configured for.

The river material renders just, which is what’s important here.