wormholes are not automatically created islandhopping

I would like to play the DS adventure map archipel, so I put this into modworldgenmain:

AddStartLocation("adv4", {
    name = "adv4",
    location = "forest",
    start_setpeice  =  "ThisMeansWarStart",	
    start_node  =  "BGGrass",
})


AddTaskSetPreInitAny(function(tasksetdata)
    if tasksetdata.location ~= "forest" then 
        return
    end
    
        tasksetdata.numoptionaltasks = 0
        tasksetdata.tasks = {"IslandHop_Start","IslandHop_Hounds","IslandHop_Forest","IslandHop_Savanna","IslandHop_Rocky","IslandHop_Merm",}
        tasksetdata.optionaltasks = {}
        tasksetdata.set_pieces = {}
        tasksetdata.substitutes = GetRandomSubstituteList(SUBS_1, 3)
        tasksetdata.ordered_story_setpieces = teleportato_layouts
        tasksetdata.required_prefabs = {
            "teleportato_ring",  "teleportato_box",  "teleportato_crank", "teleportato_potato", "teleportato_base", "chester_eyebone"
        }
        tasksetdata.overrides={
            islands = "always",
            roads = "never",
            weather = {"rare", "default", "often"},
            dragonfly  =  "never",
            bearger  =  "never",
            goosemoose  =  "never",
            season_start = "default",
            wormhole_prefab = "wormhole",
            layout_mode = "LinkNodesByKeys",
            start_location = "adv4",
            autumn = "shortseason",
            winter = "shortseason",
            spring = "shortseason",
            summer = "shortseason",
		}
}

But the world does not load, because of too many unconnected tiles.
I also tried to add a multiplayerportal and spawnpoint_master to the start setpeice.

GetWormHolesExtra:

If I add the following, the world loads without problems, but of course also without islands:
 

islandtasks = {"IslandHop_Start","IslandHop_Hounds","IslandHop_Forest","IslandHop_Savanna","IslandHop_Rocky","IslandHop_Merm",}
for _,tasks in pairs(islandtasks) do
   AddTaskPreInit(tasks,function(task)
       task.entrance_room = nil
   end)
end