Terrapretty 7.0.8 giving me a weird terrain splicing issue

[Haltingpoint]

In reading the update to 7.0.9 it sounds like it can cause weird issues, but I am still on 7.0.8 running 1.21.6 in a world generated on 1.20.-- or 1.21.-- (I forget). I have started exploring by boat, and as the fog on the map peeled away, I was left with this weirdness below where the snowing area on the left seems like a completely different map spliced in. Rowing alongside it, entire mountains are cleaved cleanly down the side, caves underwater are exposed, etc. There is also a 10C temperature differential one block over when I cross to the white side.

I notice the following error when loading the world that seems like it may be related?

3.1.2026 13:31:02 [Error] [terraprety] An exception was thrown when trying to start the mod:
3.1.2026 13:31:02 [Error] [terraprety] Exception: Patching exception in method static System.Reflection.MethodBase SmoothCoastlines.MoreContinentalUpheavalPatches::TargetMethod()
 ---> System.Exception: Method static System.Reflection.MethodBase SmoothCoastlines.MoreContinentalUpheavalPatches::TargetMethod() returned an unexpected result: null
   at HarmonyLib.PatchClassProcessor.RunMethod[S,T](T defaultIfNotExisting, T defaultIfFailing, Func`2 failOnResult, Object[] parameters)
   --- End of inner exception stack trace ---
   at HarmonyLib.PatchClassProcessor.ReportException(Exception exception, MethodBase original)
   at HarmonyLib.PatchClassProcessor.Patch()
   at HarmonyLib.Harmony.<PatchAll>b__10_0(Type type)
   at HarmonyLib.CollectionExtensions.Do[T](IEnumerable`1 sequence, Action`1 action)
   at HarmonyLib.Harmony.PatchAll(Assembly assembly)
   at HarmonyLib.Harmony.PatchAll()
   at SmoothCoastlines.SmoothCoastlinesModSystem.StartPre(ICoreAPI api)
   at Vintagestory.Common.ModLoader.TryRunModPhase(Mod mod, ModSystem system, ICoreAPI api, ModRunPhase phase) in VintagestoryLib\Common\API\ModLoader.cs:line 661
3.1.2026 13:31:02 [Error] Failed to run mod phase Pre for mod SmoothCoastlines.SmoothCoastlinesModSystem

Any suggestions as to what might be causing this, and if there is anything I can do to fix it? I already tried backing up the save and running '/wgen regen 1'  to see what would happen, it it did not neatly splice it with the existing world.

 

Edited January 3 by Haltingpoint