First one :
Config error in Sandy: onDays must be above zero
UnityEngine.StackTraceUtility:ExtractStackTrace ()
Verse.Log:Error (string)
Verse.DefDatabase`1<RimWorld.StorytellerDef>:ErrorCheckAllDefs ()
System.Reflection.RuntimeMethodInfo:Invoke (object,System.Reflection.BindingFlags,System.Reflection.Binder,object[],System.Globalization.CultureInfo)
System.Reflection.MethodBase:Invoke (object,object[])
Verse.GenGeneric:InvokeStaticMethodOnGenericType (System.Type,System.Type,string)
Verse.PlayDataLoader/<>c:<DoPlayLoad>b__4_1 (System.Type)
System.Threading.Tasks.Parallel/<>c__DisplayClass33_0`2<System.Type, object>:<ForEachWorker>b__0 (int)
System.Threading.Tasks.Parallel/<>c__DisplayClass19_0`1<object>:<ForWorker>b__1 (System.Threading.Tasks.RangeWorker&,int,bool&)
System.Threading.Tasks.TaskReplicator/Replica`1<System.Threading.Tasks.RangeWorker>:ExecuteAction (bool&)
System.Threading.Tasks.TaskReplicator/Replica:Execute ()
System.Threading.Tasks.TaskReplicator/Replica/<>c:<.ctor>b__4_0 (object)
System.Threading.Tasks.Task:InnerInvoke ()
System.Threading.Tasks.Task:Execute ()
System.Threading.Tasks.Task:ExecutionContextCallback (object)
System.Threading.ExecutionContext:RunInternal (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,bool)
System.Threading.ExecutionContext:Run (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,bool)
System.Threading.Tasks.Task:ExecuteWithThreadLocal (System.Threading.Tasks.Task&)
System.Threading.Tasks.Task:ExecuteEntry (bool)
System.Threading.Tasks.Task:System.Threading.IThreadPoolWorkItem.ExecuteWorkItem ()
System.Threading.ThreadPoolWorkQueue:Dispatch ()
System.Threading._ThreadPoolWaitCallback:PerformWaitCallback ()

Second one:
Config error in Sandy: minSpacingDays too high compared to max number of incidents.
UnityEngine.StackTraceUtility:ExtractStackTrace ()
Verse.Log:Error (string)
Verse.DefDatabase`1<RimWorld.StorytellerDef>:ErrorCheckAllDefs ()
System.Reflection.RuntimeMethodInfo:Invoke (object,System.Reflection.BindingFlags,System.Reflection.Binder,object[],System.Globalization.CultureInfo)
System.Reflection.MethodBase:Invoke (object,object[])
Verse.GenGeneric:InvokeStaticMethodOnGenericType (System.Type,System.Type,string)
Verse.PlayDataLoader/<>c:<DoPlayLoad>b__4_1 (System.Type)
System.Threading.Tasks.Parallel/<>c__DisplayClass33_0`2<System.Type, object>:<ForEachWorker>b__0 (int)
System.Threading.Tasks.Parallel/<>c__DisplayClass19_0`1<object>:<ForWorker>b__1 (System.Threading.Tasks.RangeWorker&,int,bool&)
System.Threading.Tasks.TaskReplicator/Replica`1<System.Threading.Tasks.RangeWorker>:ExecuteAction (bool&)
System.Threading.Tasks.TaskReplicator/Replica:Execute ()
System.Threading.Tasks.TaskReplicator/Replica/<>c:<.ctor>b__4_0 (object)
System.Threading.Tasks.Task:InnerInvoke ()
System.Threading.Tasks.Task:Execute ()
System.Threading.Tasks.Task:ExecutionContextCallback (object)
System.Threading.ExecutionContext:RunInternal (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,bool)
System.Threading.ExecutionContext:Run (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,bool)
System.Threading.Tasks.Task:ExecuteWithThreadLocal (System.Threading.Tasks.Task&)
System.Threading.Tasks.Task:ExecuteEntry (bool)
System.Threading.Tasks.Task:System.Threading.IThreadPoolWorkItem.ExecuteWorkItem ()
System.Threading.ThreadPoolWorkQueue:Dispatch ()
System.Threading._ThreadPoolWaitCallback:PerformWaitCallback ()

after alot of digging I figured out that this mod adds a storyteller, but it's unlisted when starting a game. So the question is, why is it there?

Cheers and thanks for the mod :)