I am trying to do integration between Openlayers and Cesium while also trying to add additional imageries. When i use OLCesium, the 2d imagery (raster and vector) gets synchronized well, but every ImageryLayer I add directly to the cesium scene doesnt get displayed at all. The same goes for primitives i add to the cesium scene. Is there a reason why custom ImageryLayers mignt not get displayed with OlCesium?