Teamwork on the same level

In order to make designer and artist and programmer work together, we split the level as 3level: lighting/sound/main level; the main level is persistent level, others as sub level(Collaborate with Sublevels).
But the problem is different level can’t directly reference others level actor. Such as the main level fire a sound or change lights setting at runtime but the sounds/lights on the other level.
Currently we use interface to notify others level whats happening, and the listening sub level hooks event and execute the action. This make gameplay logic become more complex and increase runtime cost.
In this solution, how u guys to slove the team work problem.
Or the engine support a solution to make the special sublevel can migrate together, make the “leader level” can directly access its nostreaming sublevel actor.

Supposedly you should be able to communicate between sub-levels if they are set to Always Loaded according to the docs, but I haven’t found this to be true.

Hi, Ben:
Collaborate With Sublevels is now we working between teammates. The big problem is U cannot reference another levels actor in blueprint directly and No matter the stream method.