Hi, I’ve been building a big map ( 25 km2 ) over a year now that I inherited from Gaea. I have many rivers as water splines,3 huge lakes and an ocean. 1 big lake was appearing right until I added 2 other to the map (which are far away from each other). Now when I press play, all big lakes disappear, rivers appear fine even from a far distance. Underwater effects work fine but when the camera is out of the water, MC swims in the air 
I added large planes with engine water material to make up for it but they do disappear as well (even with a regular single color material. But when I swim enough to the pivot point (at the center) it re-appears again. So I think my problem is distance to the center (or pivot point) My landscape scale is bit weird as well x: 250 y:250 z:1500. (sculpting is a pain sometimes but nothing I can not manage) can it also be related to that?
How can I keep all seas and lakes loaded at all times?
Is there a node like “keep loaded” or " keep rendered" , “keep visible, drawn, culled, etc” or sth like that? (tried avoid cull distance, draw distence settings, did not work, everything is set to visible)
I’m still learning as I go so all opinions welcome. Thanks in advance…
( IMPORTANT: My map can not be converted to world partition system, map is half full with all kinds of assets, instances and packed level actors, bit late for that I’m afraid or is it? World composition can be activated but don’t know how to use it for this… )