There's a weird bug that happens when I try to spawn, it keeps killing me right after I spawn. Do you know why this happens?

Thanks, great idea. Now you can avoid getting stuck in lava while tradertime. But I used the teleportation delay, not the trigger collision change. Thus, you can return to the playable area at any time, even in God mode, without using the Fly command.

Map looks pretty interesting.
If you want to make the lava safe during tradertime you could build a trigger volume above it and teleport player back to the playable area. Set the collision of this triggervolume to "no collision" at wavestart and back to default during tradertime. If you want the teleport point closer to the place where the player fall you could build multiple of these volumes, e.g. 6x6 over the complete lava area.