diff --git a/metadata_utils.py b/metadata_utils.py
index b3450b1..416b096 100644
--- a/metadata_utils.py
+++ b/metadata_utils.py
@@ -98,7 +98,9 @@ def find_model_file(model_name: str, model_type: str) -> Optional[Path]:
         Path to model file or None if not found
     """
     candidate_names = [model_name]
-    if "." not in Path(model_name).name:
+    known_model_suffixes = {".safetensors", ".ckpt", ".pt", ".pth", ".bin", ".gguf"}
+    suffix = Path(model_name).suffix.lower()
+    if suffix not in known_model_suffixes:
         candidate_names.append(f"{model_name}.safetensors")
 
     # Get search paths
@@ -460,8 +462,11 @@ def build_metadata_sources(manual_inputs: dict, extracted: dict, fields: List[st
     for field in fields:
         manual_value = manual_inputs.get(field)
         extracted_value = extracted.get(field)
-        if manual_value is not None and not (isinstance(manual_value, str) and not manual_value.strip()):
-            sources[field] = "manual_override"
+        if manual_value is not None:
+            if isinstance(manual_value, str) and not manual_value.strip():
+                sources[field] = "unknown"
+            else:
+                sources[field] = "manual_override"
         elif extracted_value is not None and not (isinstance(extracted_value, str) and not extracted_value.strip()):
             sources[field] = "detected"
         else:
@@ -1000,6 +1005,7 @@ def _sanitize_relative_segments(path_text: str) -> Path:
     normalized = path_text.replace("\\", "/")
     if _has_drive_or_root(normalized):
         raise ValueError(f"Absolute paths are not allowed here: {path_text!r}")
+    normalized = normalized.rstrip("/")
     raw_segments = normalized.split("/")
     if any(segment == "" for segment in raw_segments):
         raise ValueError(f"Empty path segments are not allowed: {path_text!r}")
diff --git a/tests/test_metadata_utils.py b/tests/test_metadata_utils.py
index 242d0d8..c2fbbc1 100644
--- a/tests/test_metadata_utils.py
+++ b/tests/test_metadata_utils.py
@@ -11,6 +11,7 @@ from metadata_utils import (
     build_metadata_status,
     ensure_metahub_save_node,
     ensure_prompt_in_workflow,
+    find_model_file,
     get_next_filename,
     get_output_directory,
     get_workflow_json,
@@ -58,6 +59,20 @@ def test_output_path_relative_resolves_under_comfy_output(tmp_path, monkeypatch)
     assert output.exists()
 
 
+def test_output_path_allows_trailing_separator(tmp_path, monkeypatch):
+    class FakeFolderPaths:
+        @staticmethod
+        def get_output_directory():
+            return str(tmp_path / "output")
+
+    monkeypatch.setitem(sys.modules, "folder_paths", FakeFolderPaths)
+
+    output = get_output_directory("project/")
+
+    assert output == tmp_path / "output" / "project"
+    assert output.exists()
+
+
 def test_filename_pattern_supports_subfolders_and_tokens():
     params = {"seed": 123, "model_name": "model.safetensors"}
 
@@ -98,6 +113,27 @@ def test_metadata_status_marks_defaulted_fields_as_partial():
     assert build_metadata_status(sources, ["positive", "model_name", "seed"]) == "partial"
 
 
+def test_blank_string_override_is_unknown_not_detected():
+    sources = build_metadata_sources(
+        {"positive": ""},
+        {"positive": "extracted prompt"},
+        ["positive"],
+    )
+
+    assert sources["positive"] == "unknown"
+    assert build_metadata_status(sources, ["positive"]) == "fallback"
+
+
+def test_find_model_file_tries_safetensors_for_dotted_extensionless_names(tmp_path, monkeypatch):
+    model_dir = tmp_path / "models"
+    model_dir.mkdir()
+    model_path = model_dir / "dreamshaper.v8.safetensors"
+    model_path.write_bytes(b"model")
+    monkeypatch.setenv("COMFYUI_CHECKPOINT_PATH", str(model_dir))
+
+    assert find_model_file("dreamshaper.v8", "checkpoint") == model_path
+
+
 def test_ensure_prompt_in_workflow_adds_prompt():
     workflow = {"workflow": {"nodes": []}}
     prompt = {"1": {"class_type": "KSampler", "inputs": {}}}
diff --git a/tests/test_video_metadata_utils.py b/tests/test_video_metadata_utils.py
index 6961c4d..ec193cb 100644
--- a/tests/test_video_metadata_utils.py
+++ b/tests/test_video_metadata_utils.py
@@ -44,3 +44,19 @@ def test_video_metadata_nulls_defaulted_canonical_fields():
     assert payload["prompt"] is None
     assert payload["model"] is None
     assert payload["seed"] is None
+
+
+def test_video_metadata_nulls_unknown_blank_overrides():
+    payload = build_video_metahub_metadata(
+        {
+            "positive": "",
+            "width": 640,
+            "height": 480,
+            "metadata_sources": {
+                "positive": "unknown",
+            },
+        },
+        {},
+    )
+
+    assert payload["prompt"] is None
diff --git a/video_metadata_utils.py b/video_metadata_utils.py
index eee7616..b557d9e 100644
--- a/video_metadata_utils.py
+++ b/video_metadata_utils.py
@@ -209,7 +209,7 @@ def build_video_metahub_metadata(params: dict, workflow_json: dict) -> dict:
     sources = params.get("metadata_sources") if isinstance(params.get("metadata_sources"), dict) else {}
 
     def canonical(field: str, param_key: str, fallback: Any = None) -> Any:
-        if sources.get(field) == "default":
+        if sources.get(field) in {"default", "unknown"}:
             return None
         return params.get(param_key, fallback)