Two validation errors fixed: 1. imageCubeArray feature not enabled → added VkPhysicalDeviceImageCubeArrayFeatures to device creation chain (pNext: cubeArray → sync2 → dynamicRendering) 2. Shadow layers 18-23 in UNDEFINED layout → transition ALL 24 layers (MaxShadowLights * 6) instead of only numShadowLights * 6 Descriptor references all 24 layers via CubeArray view