You're spawning in the middle of the ocean cause you're using a grid cell as home server when it's not, so it lacks the spawn points thus using the default [0.0] and that's usually in the middle of nowhere, instead of that grid, for a 2 server config try [0,0] for home server and [0,1] for slave server and see how it goes,also another way is just going to the editor and make your own 2 grid map, it's a bit tricky but it may be the best solution and it's good to be able to make your map, your way. hope i helped in any way!
A solution doesnt come to my mind, i've been trashing around with the map editor and i cant find an option to make non square maps, so i think the only thing you could do with 5 servers is use a bigger square grid, like a 3x3 and then use the grids you want, for example [0,0][0,1][0,2][1,0][1,1] or whatever u see fit.
So I noticed from my experience years before, the box check that enabled flying in caves disappeared, i've read its authomatic still in my server is forbidden, so I used this options on the custom game.ini at the end of the yellow " modify servers settings":
[serverSettings]
ShowFloatingDamageText=true
ForceAllowCaveFlyers=True
ShowMapPlayerLocation=True
The floating damage and location is okay, working fine, the cave flying is not. I checked and these options are indeed written into the ini. Actually GameUserSettings.ini but it's the only option not working, any hints on this?