This happens when the game master is:

A) Off host, meaning the GM or a Zeus enabled player is not the host of the game
B) Assets are on screen

In the null forest or off map, the fps is about cut in half. I get about 40 fps when nothing is near me, but as soon as the terrain, buildings, trees, etc, enter the view port, then the fps goes down to terrible levels, making zeus un-playable for people who are not hosting the server.

The FPS drops also effect the players as well, in most cases, but I'm not quite sure if it effects the host if he is in the player slot.

Also, its not map bound. I've tested zeus on other maps (chanarus, namalisk, etc) and they all have the same problem.

The issue with lag causes it so you can't 'UAV control' units when you are zeus, in game logic zeus mode (vs player entity zeus mode)