Is it possible to completely hide some objects in your scene when they are at certain distance? I mean not sending any batch to the GPU at all for them? Or in other words, can LODs use empty nodes. What about animated models (Actors)?
On the LODNode you set the show and hide distance for each LOD, so you if you just wanted to use it to hide an object at a certain distance you would just have one LOD on it with a near distance of 0 and far distance of however far you wanted it to disappear at. There is no need to make an LOD level with a empty node, it will just be not showing any node.
Actor has its own LOD system, but you might need to look through the code to figure out how to use it.