Raids not spawning.

[Rodsoldier]

At first i had problems getting visitors to spawn (for 4 years)m then, tweaking the order of hospitality and giddyup i got them to. 
And i think raids were still spawning. 
But now they stopped, after no considerable further change was made. 
I can force them to spawn. 
Skipping seasons makes visitors come but doesn't spawn any raids, is that standart? 
Thanks in advance.

I get spam of this error on the log.

System.NullReferenceException: Object reference not set to an instance of an object
  at RimWorld.NeutralGroupIncidentUtility.AnyBlockingHostileLord (Verse.Map map, RimWorld.Faction forFaction) [0x00000] in <filename unknown>:0
  at RimWorld.IncidentWorker_TraderCaravanArrival.CanFireNowSub (RimWorld.IncidentParms parms) [0x00000] in <filename unknown>:0
  at RimWorld.IncidentWorker.CanFireNow (RimWorld.IncidentParms parms, Boolean forced) [0x00000] in <filename unknown>:0
  at RimWorld.Storyteller.TryFire (RimWorld.FiringIncident fi) [0x00000] in <filename unknown>:0
  at RimWorld.IncidentQueue.IncidentQueueTick () [0x00000] in <filename unknown>:0
  at RimWorld.Storyteller.StorytellerTick () [0x00000] in <filename unknown>:0
  at Verse.TickManager.DoSingleTick () [0x00000] in <filename unknown>:0
Verse.Log:Error(String, Boolean)
Verse.TickManager:DoSingleTick()
Verse.TickManager:TickManagerUpdate()
Verse.Game:UpdatePlay()
Verse.Root_Play:Update()

[Canute]

At first we had problems getting visitors to read stickies topic's first before they post.
Since you use mod's it isn't a vanila bug, more an issue with a mod.

Some Incident cause problem, and can't be exceuted. TraderCaravanArrival is the keyword here.
You can edit your safegame. Backup it before.
Open it with a texteditor.
Search 2 times for <incidentQueue>
Then you see a list of incident's.
It should be the first or second, maybe you see the word trader there.
Delete from <li> to </li>

But that don't prevent the same error appear later again.
You should update all mod's if you don't use steam, special the giddyup series.

[Taur-nu-Fuin]

Just Wanna say I made an account to thank you for making my save game playable again. Just recently this error showed up and I had no idea how I was going to proceed, I use Steam as well so I think this is an error due to some mod incompatibilities that had not shown up previously but will probably show up more often so it will get fixed soon (least I hope!)

[SonOfNitrous]

At first we had problems getting visitors to read stickies topic's first before they post.
Since you use mod's it isn't a vanila bug, more an issue with a mod.

Some Incident cause problem, and can't be exceuted. TraderCaravanArrival is the keyword here.
You can edit your safegame. Backup it before.
Open it with a texteditor.
Search 2 times for <incidentQueue>
Then you see a list of incident's.
It should be the first or second, maybe you see the word trader there.
Delete from <li> to </li>

But that don't prevent the same error appear later again.
You should update all mod's if you don't use steam, special the giddyup series.

sorry for dumb question... but should I delete with <li> to </li> or everything between?

thx in advance!

[Canute]

with <li> to </li> !