"A guest world that guests spawn on and cannot leave. And once they are memebrs, is it possible for the /spawn command to take them to the Members group spawn on another world? Or how do they get to the members world once they are of that rank?" (request from a user)
First, we'll setup some assumptions about your permissions (mentally map to your own configuration). We'll assume new folks come in at some default rank we'll call group "Guest". We'll assume they can be promoted to group "Members". To add some variety, we'll also assume you have a group "VIP" and you want your VIPs to go to their own VIP spawn instead of the member one.
On your guest world, you can "/setfirstspawn" wherever it is that you want the guests to spawn. On your Members world, you can "/setgroupspawn Members" to setup the Members group spawn and "/setgroupspawn VIP" to setup the VIP group spawn. Now here is the config to make it all work:
# config.yml events: onJoin: # first-time players go to new player spawn - spawnNewPlayer # otherwise we just let Bukkit put players wherever they last # logged out - default onDeath: - homeLocalWorld - spawnLocalWorld # your choice whether they have /spawn command or not, but this keeps # them on the same world onSpawnCommand: - spawnLocalWorld permissions: entry1: # you must assign this permission to your "Members" group permissions: - group.Members # when a member types /spawn, send them to their groupspawn on # world "main" onSpawnCommand: - spawnGroupSpecificWorld:main entry2: # you must assign this permission to your "VIP" group permissions: - group.VIP # when a VIP types /spawn, send them to their groupspawn on # world "main" onSpawnCommand: - spawnGroupSpecificWorld:main