Should we still use World Composition ?

If the machine takes time to load the streaming level, the character will fall. Maybe you should do as I do : try to trace for the ground and wait if it’s not here yet.
But yes, documentation est very thin. Like Procedural Foliage in World Composition : the options are not explained and nothing is said about how to optimize instances, how to limit usage and maybe not have every tree of the same type in the same instance, making it’s destruction at runtime impossible (or HUGE lag). Or how to radial collide with foliage damage… but It’s off-topic.