Looks like hardware raytracing itself might be bugged this patch. Does this issue apply to other fresh sample projects as well? I’m seeing incompatibilities with the water plugin + megalights even if disabled. If it does apply to everything, I’d first try verifying the engine just as a precaution, updating GPU drivers, and testing on other projects as well just to verify it’s global. If it is and can be reproduced, I would submit a bug here: