Same problem here,

Here's what came out my error log,

https://gist.github.com/74250bc221c44ac7ec6f803788f617aa

Just to see if its the same thing

I have this same bug. Hopefully someone will figure it out, I like the searchlight.

Exception in UIRootUpdate: System.NullReferenceException: Object reference not set to an instance of an object
at RimWorld.PlaceWorker_ShowTurretRadius.AllowsPlacing (Verse.BuildableDef checkingDef, Verse.IntVec3 loc, Verse.Rot4 rot, Verse.Map map, Verse.Thing thingToIgnore, Verse.Thing thing) [0x0003a] in <642567a9bd804f26a9090d82e2c3673d>:0
at (wrapper dynamic-method) RimWorld.GenConstruct.DMD<DMD<CanPlaceBlueprintAt_Patch2>?2141348480::CanPlaceBlueprintAt_Patch2>(Verse.BuildableDef,Verse.IntVec3,Verse.Rot4,Verse.Map,bool,Verse.Thing,Verse.Thing,Verse.ThingDef)
at (wrapper dynamic-method) RimWorld.Designator_Build.DMD<DMD<CanDesignateCell_Patch2>?228849792::CanDesignateCell_Patch2>(RimWorld.Designator_Build,Verse.IntVec3)
at RimWorld.Designator_Place.SelectedUpdate () [0x00035] in <642567a9bd804f26a9090d82e2c3673d>:0
at RimWorld.Designator_Build.SelectedUpdate () [0x00000] in <642567a9bd804f26a9090d82e2c3673d>:0
at Verse.DesignatorManager.DesignatorManagerUpdate () [0x00013] in <642567a9bd804f26a9090d82e2c3673d>:0
at (wrapper dynamic-method) RimWorld.MapInterface.DMD<DMD<MapInterfaceUpdate_Patch1>?1332962816::MapInterfaceUpdate_Patch1>(RimWorld.MapInterface)

Is the likely relevant error from the above error log, comments are showing it as happening for all/most installs.

I have this same bug, only it's in the Rocket turret and catapult

Also experiencing this bug

Same error

The rocket turrets doesn't work. I think the spotlights and catapult are also broken. I don't know where i can put the logs, so i'll post it here.
https://gist.github.com/91a6fb193b159e8e9454fa506a76a05b

Everything but the spotlight is broken because of mortar accuracy. Replace it with xnd turret extensions.

same thing here. can't place the searchlight.

Should have been fixed yesterday. Please update the mod and enjoy working searchlights.

problem still persists with rocket turrets

Having the problem with rocket turrets as well

Same thing with rocket turrets

Ye same here with rocket turret

fifth for turrets. weirdly works if built into a wall but otherwise i cant place blueprints