How would I go about setting up free for all spawns on a small, open map? Do respawn zones apply in FFA? If they don't could I get some tips? I have a few screenshots to help you get an idea: Thanks in advance.
I'm not big on FFA maps, but I would suggest thinking about where a majority of the combat will take place, and place the spawns safely out of combat but in a location that can easily access the fray. For example, the far right side, far bottom, and top right (In your second image) all seem to be good places based on the image. Also, I would make sure they are at least spawned with a reasonable amount of cover, perhaps a small rock. As to the FFA spawn zones, I have no idea, I don't usually do anything with FFA maps other than play on some made by friends.
To the best of my knowledge, only Neutral-owned Zones are applied in FFA. So to get team and FFA spawns, you set all Respawn Points to Neutral and use team-owned Respawn Zones to assign them to teams in team gametypes. This has the advantage of allowing you to vary which spawns are owned by which teams on a per-gametype basis. Note that team-owned Respawn Zones will not re-assign Initial Spawn Points. There are a number of ways to handle this situation, i.e. FFA_ONLY and TEAM_ONLY Initial Spawn Points.
I guess that that map is yours, so just out some spawns at the wall. Spawns should be placed towards a direction you want the players to move, or facing a key point of the map. May I suggest you put in a little more cover on your map, just for the spawning?