diff --git a/amulet/api/wrapper/format_wrapper.py b/amulet/api/wrapper/format_wrapper.py
index 7a20e7bc2..94d4e91b5 100644
--- a/amulet/api/wrapper/format_wrapper.py
+++ b/amulet/api/wrapper/format_wrapper.py
@@ -232,7 +232,7 @@ def bounds(self, dimension: Dimension) -> SelectionGroup:
         if dimension not in self._bounds:
             if dimension in self.dimensions:
                 raise Exception(
-                    f'The dimension exists but there is not selection registered for it. Please report this to a developer "{dimension}" {self}'
+                    f'The dimension exists but there is no selection registered for it. Please report this to a developer "{dimension}" {self}'
                 )
             else:
                 raise DimensionDoesNotExist
diff --git a/amulet/level/formats/anvil_forge_world.py b/amulet/level/formats/anvil_forge_world.py
index bf3a77d4c..e06141a40 100644
--- a/amulet/level/formats/anvil_forge_world.py
+++ b/amulet/level/formats/anvil_forge_world.py
@@ -1,4 +1,5 @@
 from __future__ import annotations
+import glob
 import os
 
 from amulet_nbt import load as load_nbt
@@ -24,7 +25,9 @@ def is_valid(path: str) -> bool:
         except:
             return False
 
-        return "Data" in level_dat_root and "FML" in level_dat_root
+        return "Data" in level_dat_root and (
+            "FML" in level_dat_root or "fml" in level_dat_root
+        )
 
     @property
     def game_version_string(self) -> str:
diff --git a/amulet/level/formats/anvil_world/format.py b/amulet/level/formats/anvil_world/format.py
index 3dc950cb5..26587b4ce 100644
--- a/amulet/level/formats/anvil_world/format.py
+++ b/amulet/level/formats/anvil_world/format.py
@@ -412,15 +412,20 @@ def _reload_world(self):
                     continue
                 self._register_dimension(dir_name)
 
-        for dimension_path in glob.glob(
-            os.path.join(glob.escape(self.path), "dimensions", "*", "*", "region")
+        for region_path in glob.glob(
+            os.path.join(
+                glob.escape(self.path), "dimensions", "*", "*", "**", "region"
+            ),
+            recursive=True,
         ):
-            dimension_path_split = dimension_path.split(os.sep)
-            dimension_name = f"{dimension_path_split[-3]}:{dimension_path_split[-2]}"
-            self._register_dimension(
-                os.path.dirname(os.path.relpath(dimension_path, self.path)),
-                dimension_name,
-            )
+            if not os.path.isdir(region_path):
+                continue
+            dimension_path = os.path.dirname(region_path)
+            rel_dim_path = os.path.relpath(dimension_path, self.path)
+            _, dimension, *base_name = rel_dim_path.split(os.sep)
+
+            dimension_name = f"{dimension}:{'/'.join(base_name)}"
+            self._register_dimension(rel_dim_path, dimension_name)
 
     def _open(self):
         """Open the database for reading and writing"""