diff --git a/invokeai/backend/model_manager/configs/main.py b/invokeai/backend/model_manager/configs/main.py
index b2ce766f37..cd4a580802 100644
--- a/invokeai/backend/model_manager/configs/main.py
+++ b/invokeai/backend/model_manager/configs/main.py
@@ -126,9 +126,12 @@ def _has_z_image_keys(state_dict: dict[str | int, Any]) -> bool:
         if isinstance(key, int):
             continue
         # Check for Z-Image specific key prefixes
-        prefix = key.split(".")[0]
-        if prefix in z_image_specific_keys:
-            return True
+        # Handle both direct keys (cap_embedder.0.weight) and
+        # ComfyUI-style keys (model.diffusion_model.cap_embedder.0.weight)
+        key_parts = key.split(".")
+        for part in key_parts:
+            if part in z_image_specific_keys:
+                return True
     return False
 
 
diff --git a/invokeai/backend/model_manager/load/model_loaders/z_image.py b/invokeai/backend/model_manager/load/model_loaders/z_image.py
index e7e0813073..2668607a7d 100644
--- a/invokeai/backend/model_manager/load/model_loaders/z_image.py
+++ b/invokeai/backend/model_manager/load/model_loaders/z_image.py
@@ -41,6 +41,7 @@ def _convert_z_image_gguf_to_diffusers(sd: dict[str, Any]) -> dict[str, Any]:
     - k_norm.weight -> norm_k.weight
     - x_embedder.* -> all_x_embedder.2-1.*
     - final_layer.* -> all_final_layer.2-1.*
+    - norm_final.* -> skipped (diffusers uses non-learnable LayerNorm)
     """
     new_sd: dict[str, Any] = {}
 
@@ -63,6 +64,11 @@ def _convert_z_image_gguf_to_diffusers(sd: dict[str, Any]) -> dict[str, Any]:
             new_sd[new_key] = value
             continue
 
+        # Skip norm_final keys - the diffusers model uses LayerNorm with elementwise_affine=False
+        # (no learnable weight/bias), but some checkpoints (e.g., FP8) include these as all-zeros
+        if key.startswith("norm_final."):
+            continue
+
         # Handle fused QKV weights - need to split
         if ".attention.qkv." in key:
             # Get the layer prefix and suffix
@@ -185,16 +191,19 @@ class ZImageCheckpointModel(ModelLoader):
         # Load the state dict from safetensors/checkpoint file
         sd = load_file(model_path)
 
-        # Some Z-Image checkpoint files have keys prefixed with "diffusion_model."
-        # Check if we need to strip this prefix
-        has_prefix = any(k.startswith("diffusion_model.") for k in sd.keys() if isinstance(k, str))
+        # Some Z-Image checkpoint files have keys prefixed with "diffusion_model." or
+        # "model.diffusion_model." (ComfyUI-style format). Check if we need to strip this prefix.
+        prefix_to_strip = None
+        for prefix in ["model.diffusion_model.", "diffusion_model."]:
+            if any(k.startswith(prefix) for k in sd.keys() if isinstance(k, str)):
+                prefix_to_strip = prefix
+                break
 
-        if has_prefix:
+        if prefix_to_strip:
             stripped_sd = {}
-            prefix = "diffusion_model."
             for key, value in sd.items():
-                if isinstance(key, str) and key.startswith(prefix):
-                    stripped_sd[key[len(prefix) :]] = value
+                if isinstance(key, str) and key.startswith(prefix_to_strip):
+                    stripped_sd[key[len(prefix_to_strip) :]] = value
                 else:
                     stripped_sd[key] = value
             sd = stripped_sd
@@ -236,6 +245,12 @@ class ZImageCheckpointModel(ModelLoader):
         new_sd_size = sum([ten.nelement() * model_dtype.itemsize for ten in sd.values()])
         self._ram_cache.make_room(new_sd_size)
 
+        # Filter out FP8 scale_weight and scaled_fp8 metadata keys
+        # These are quantization metadata that shouldn't be loaded into the model
+        keys_to_remove = [k for k in sd.keys() if k.endswith(".scale_weight") or k == "scaled_fp8"]
+        for k in keys_to_remove:
+            del sd[k]
+
         # Convert to target dtype
         for k in sd.keys():
             sd[k] = sd[k].to(model_dtype)
@@ -284,16 +299,19 @@ class ZImageGGUFCheckpointModel(ModelLoader):
         # Load the GGUF state dict
         sd = gguf_sd_loader(model_path, compute_dtype=compute_dtype)
 
-        # Some Z-Image GGUF models have keys prefixed with "diffusion_model."
-        # Check if we need to strip this prefix
-        has_prefix = any(k.startswith("diffusion_model.") for k in sd.keys() if isinstance(k, str))
+        # Some Z-Image GGUF models have keys prefixed with "diffusion_model." or
+        # "model.diffusion_model." (ComfyUI-style format). Check if we need to strip this prefix.
+        prefix_to_strip = None
+        for prefix in ["model.diffusion_model.", "diffusion_model."]:
+            if any(k.startswith(prefix) for k in sd.keys() if isinstance(k, str)):
+                prefix_to_strip = prefix
+                break
 
-        if has_prefix:
+        if prefix_to_strip:
             stripped_sd = {}
-            prefix = "diffusion_model."
             for key, value in sd.items():
-                if isinstance(key, str) and key.startswith(prefix):
-                    stripped_sd[key[len(prefix) :]] = value
+                if isinstance(key, str) and key.startswith(prefix_to_strip):
+                    stripped_sd[key[len(prefix_to_strip) :]] = value
                 else:
                     stripped_sd[key] = value
             sd = stripped_sd