My initial idea was to have bots perform a halo jump, running out of the back of a plane from high altitude, but I can't figure out pathfinding to save my life, so I decided that the easiest way to get the same effect was drop them.
The real reason I wanted to have a spawn point so high up was so the player could choose to skydive right down to the target and take on the entire enemy team by themselves until friendly bots land.
RECOMMENDED BOTS: 40-60, depending on how many guns you want aimed at you while you slowly float down from the sky.
If you want to play on SKIRMISH mode, set duration to SHORT. Enemy reinforcements will spawn above the UFO's and sit on top. Again, I don't understand pathfinding.