Some 3D objects not animating

Hi

I have some objects in my model which wont animate/follow the 3D path. I have tried adjusting the alignment (i,e centre/custom). Tried different types of 3D paths. I haven even tried to load the model into a fresh project and create new tasks but still no luck. It is bathroom pods which I want to show dropping from the sky. Slabs and precast planks all work as they should. Columns seem to be temperamental too. Some will animate and some wont. Any ideas?

Thanks

Stephen