I did the update of Waveworks from 4.19 to 4.21 then worked with to merge it into his branch. I didn’t realize the BP_WaterPlane isn’t working since I don’t use that, and didn’t test that blueprint. I don’t have time right now to dig into it, but I’ll take a look at it for the next update.
From the errors posted previously (BufferRHI was nullptr), it looks like the WaterPlane BP uses a different uniform buffer that needs to be updated to follow the changes in the rendering engine that happened between 4.19 and 4.21. If someone wants to look into it, I’d suggest starting by looking at the changes I made in TranslucentRendering.cpp in the function void FDeferredShadingSceneRenderer::RenderWaveWorks. Then see if you can determine from the stack trace debugging in VS what function is getting called that needs to be updated.
You can use the 4.19 version of Waveworks to save the BP_WaterPlane with visibility of the waterplane turned off. Then use that for debugging the 4.21 branch. That makes it easier for debugging in VS, since the project will load correctly, and you can trigger the error simply by checking the visibility checkbox.