I've been on PS2 servers where the exact initial spawn points for each soldier was changed.

To be specific, in Polis Massa the empire and republic will spawn in the hangar, although they
selected the middle command post.

I've seen it modified to the point, they actually spawn in the room with the CP to help meet the enemy on an equal travel distance.

The only tip I ever got was use zero editor.

My only idea was to load the .lvl map files from the server into zeroeditor.

But zeroeditor crashes upon loading the map, I assume it's not meant to open .lvl stuff.

It's a small and unimportant thing, but with the know-how I could get humans, and bots to spawn on roof tops and in walls and stuff for some crazy results.

If the PS2 maps are the same as the PC maps, then you could use the Polis Massa map assets and edit the spawn points using ZE. Then you could munge the edited map and find the new lvl file that contains the map data and then load them into your server (or however you would get a modified lvl into your server).

Couldn't you just edit it via lua? Not sure if that's "better", but you could use setproperty (I think that's the one?) to change the spawn path used for each cp. Ie. You could make cp7 use cp3's spawns by lua edits. If you want to add completely new spawn points, you'd have to do what Noobasaurus said...

I used to be pretty good at modding the stuff of Ps2. Nothing major, but I never used ZeroEditor to mod the maps. I always used a hexeditor on the server .lvls and whatnot. You just have to know what to search for that you want to change (IE; if you wanted to make a blaster shoot a cone of bullets, you would have to have the ODF name of the blaster aforementioned and search for that in the hexeditor. There are also a lot of places with the same thing that you will have to find and change). The spawn point thing I had seen often but never got around to actually doing, so I can't help you much there.