I understand pretty well what containers do and are for. After rereading the manual entry for them, however, it is unclear to me how to make them. The manual refers to the "container category" in an objects properties, but I cannot find that entry. Are containers not in the free version or something? Is there some obscure setting that has to be ticked to make an object a container before the category shows up in any objects properties? What's up?
Thanks.