I have this error when i tried to remove this mod after playing with it for a day (i had a z level infestation in the mean time) this is not my first attempt at this and i used dev mode to remove any boulder, mushroom, insect and object in the underground level (didnt removed the dirt tho), then i saved the game and removed the mod, loaded the save again and this spammed until the game message limit for an error

Root level exception in Update(): System.NullReferenceException: Object reference not set to an instance of an object
at RimWorld.GenCelestial.CelestialSunGlow (Verse.Map map, System.Int32 ticksAbs) [0x00005] in <0ee2c524c4be441e9b7f8bfcb20aca6f>:0
at RimWorld.GenCelestial.CurCelestialSunGlow (Verse.Map map) [0x0000b] in <0ee2c524c4be441e9b7f8bfcb20aca6f>:0
at Verse.WeatherWorker.CurSkyTarget (Verse.Map map) [0x00000] in <0ee2c524c4be441e9b7f8bfcb20aca6f>:0
at Verse.SkyManager.CurrentSkyTarget () [0x00015] in <0ee2c524c4be441e9b7f8bfcb20aca6f>:0
at Verse.SkyManager.SkyManagerUpdate () [0x00000] in <0ee2c524c4be441e9b7f8bfcb20aca6f>:0
at Verse.Map.MapUpdate () [0x00005] in <0ee2c524c4be441e9b7f8bfcb20aca6f>:0
at (wrapper dynamic-method) Verse.Game.DMD<DMD<UpdatePlay_Patch2>?1576359808::UpdatePlay_Patch2>(Verse.Game)
at Verse.Root_Play.Update () [0x00026] in <0ee2c524c4be441e9b7f8bfcb20aca6f>:0
Verse.Log:Error(String, Boolean)
Verse.Root_Play:Update()

my modlist: https://textuploader.com/1xgww