QuinRiva

As I said in the OP, I did install all the mods that were part of the STEP Extended setup and had a CTD when I activated the STEP Extended mod. I then rolled back to the bare minimum in order to resolve the initial CTD. Testing the same mods on Nexus Mod Manager seemed to work, so I realised it must have been something specific to MO. I think I have now resolved the issue by reinstalling all of the mods that are masters to the STEP Extended Patch.esp with MO. I had reinstalled most of them, but I think there were a few that I had just reactivated not reinstalled. Potentially some time long ago I had cleaned a master that I shouldn't have, or something got corrupted.

Yes, that was what I originally did. However after getting a CTD, I tried rolling back to the absolute bare minimum and the CTD persisted. I have also tried a new install of Skyrim with the same mods and loaded with Nexus Mod Manager. This did work. I rolled back to a clean install with Mod Organizer, and CTD returns. Clearly it is something to do with the way that MO is loading things... Installation order was the same in both cases, esp load order was the same in both cases and I made sure that I cleared the MO Overwrite folder. Trying to figure out what the difference is now...

Hmm, the ini's are freshly regenerated (i.e. I just deleted the .ini's and then ran Skyrim Launcher). After I regenerated the ini's I then added all of the settings here: Guide:Skyrim_INIs. Are there some other ini settings that are required? Note, my old ini's were substantially larger, and they didn't work either, hence the regen. I have disable enb and I still get a CTD. I have also tried running by launching the Skyrim executable (instead of SKSE, same problem).

I was methodically adding the all the mods that are part of the STEP Extended set up, and everything was going fine until I enabled the STEP Extended Patch.esp (using Mod Organizer). Enabling this esp results in a CTD during the opening carriage/wagon ride - specifically at the "... same as that thief over there. -- Damn you Stormcloaks, everything was fine until" I CTD... I have tried rolling everything back so that I am using the STEP Extended patch and only the direct dependencies of the patch, and I still get a CTD. I've even ensured that the Load order in my list, matches the load order in the Extended Patch masters: [spoiler=Load Order]Skyrim.esm Update.esm Unofficial Skyrim Patch.esp Dawnguard.esm Unofficial Dawnguard Patch.esp HearthFires.esm Unofficial Hearthfire Patch.esp Dragonborn.esm Unofficial Dragonborn Patch.esp Cutting Room Floor.esp ExplosiveBoltsVisualized.esp Animated Weapon Enchants.esp Elemental Staves.esp Complete Crafting Overhaul_Remade.esp SkyrimCoinReplacerRedux.esp Bring Out Your Dead.esp ADS.esp AOS.esp RealisticWaterTwo.esp dD - Enhanced Blood Main.esp DeadlySpellImpacts.esp aMidianBorn_ContentAddon.esp Thieves Guild Requirements.esp TheChoiceIsYours.esp The Paarthurnax Dilemma.esp STEP Extended Patch.esp I've reverted the Skyrim.ini and SkyrimPrefs.ini [spoiler=Skyrim.ini][General] sIntroSequence= ;Disables the intro sequence for a faster startup fFlickeringLightDistance=8192 ;Helps prevent lighting pop-in [Display] sD3DDevice="NVIDIA GeForce GTX 670" fSunShadowUpdateTime=0.25 ;Transition time of sun-shadow movement fSunUpdateThreshold=1.5 ;Time between sun-shadow movement iPresentInterval=1 ;This line needs to be manually added, as it is misplaced into SkyrimPrefs.ini by Skyrim! - REQUIRED by ENBoost [Grass] b30GrassVS=0 iMaxGrassTypesPerTexure=7 ;increase grass diversity with a small cost to performance (yes, 'texure' and not 'texture'). Consider set to 7 if using SFO. [Combat] ;Shift the point of aim to the center of the aiming reticule for arrows and crossbows. f1PArrowTiltUpAngle=0.7 f3PArrowTiltUpAngle=0.7 f1PBoltTiltUpAngle=0.7 f3PBoltTiltUpAngle=0.7 ;this tweak is not present in the default INI and needs to be entered manually [Camera] ;Place the camera just above the character's head in third-person view, and correct the camera angle in third-person view while on horseback (from "Third Person Horse Camera") fOverShoulderAddY=0.0 fOverShoulderPosZ=18.0 fOverShoulderPosX=0.0 fOverShoulderCombatAddY=0.0 fOverShoulderCombatPosZ=24.0 fOverShoulderCombatPosX=0.0 fOverShoulderHorseAddY=-72.0 fOverShoulderHorsePosZ=50.0 fOverShoulderHorsePosX=35.0 fActorFadeOutLimit=-100 fMouseWheelZoomSpeed=60.0 ;instant camera-angle switching when switching view types or when mounting/dismounting horse (from "Instant Camera POV Switching") f1st3rdSwitchDelay=0.95 iHorseTransitionMillis=001 [interface] fBookOpenTime=200.0 ;speeds up the book-opening animation ;move the HUD elements closer to the borders of the screen fSafeZoneX=10 fSafeZoneY=10 fSafeZoneXWide=10 fSafeZoneYWide=10 [VATS] ;Increase ranged killcam frequency (or disable killcams) fVATSCastingAfterKillDelay=1.2000 uVATSRangedPercentSneak=100 uVATSRangedPercentGlobal=100 bVATSMultipleCombatants=1 bVATSForceRanged=1 bVATSDisable=1 ;enable(0) or disable (1) killcams [Water] bReflectLODObjects=1 bReflectLODLand=1 bReflectSky=1 bReflectLODTrees=1 [spoiler=SkyrimPrefs.ini][Display] iTexMipMapSkip=0 bFXAAEnabled=0 fMeshLODLevel2FadeDist=1e+007 fMeshLODLevel1FadeDist=1e+007 fSpecularLODStartFade=2000 fLightLODStartFade=3500 fTreesMidLODSwitchDist=1e+007 iShadowMapResolution=4096 fShadowBiasScale=0.15 iShadowMaskQuarter=4 iBlurDeferredShadowMask=3 fShadowDistance=8000 iMaxDecalsPerFrame=100 iMaxSkinDecalsPerFrame=25 iAdapter=0 iSize W=2560 iSize H=1600 iMultiSample=0 iMaxAnisotropy=0 bFull Screen=1 bTreesReceiveShadows=1 ;Enables shadows rendering on trees (insignificant performance impact) bDrawLandShadows=1 ;Enables shadows rendering on land (insignificant performance impact) bFloatPointRenderTarget=1 ;Set to 'one' if using deferred shader rendering ENB lighting (NOT supported by STEP). [Controls] bMouseAcceleration=0 ;Disables mouse acceleration [imagespace] iRadialBlurLevel=2 [LOD] fLODFadeOutMultActors=15 fLODFadeOutMultItems=15 fLODFadeOutMultObjects=15 [Grass] fGrassStartFadeDistance=18000 ;push back the distance for grasses to fade (minor performance hit) [Decals] bDecals=1 bSkinnedDecals=1 uMaxDecals=1000 uMaxSkinDecals=100 uMaxSkinDecalsPerActor=60 bDecalsOnSkinnedGeometry=1 ;Enable higher-res blood on NPCs (insignificant performance impact) iMaxDecalsPerFrame=256 ;increases the number of blood decals per scene (from "Enhanced Blood Textures") [TerrainManager] fTreeLoadDistance=75000 fBlockMaximumDistance=250000 fBlockLevel1Distance=70000 fBlockLevel0Distance=35000 fSplitDistanceMult=1.5 [blurShaderHDR] bDoHighDynamicRange=1 [blurShader] bUseBlurShader=0 [Launcher] bShowAllResolutions=1 uLastAspectRatio=4 I'm using the most recent versions of SKSE and ENB. Disabling the STEP Extended Patch.esp enables to the opening carriage ride to run without any problems. I've checked to ensure that the SKSE Memory patch is running fine (it is). I'm unsure what could possibly be causing the problem?