diff --git a/tests/test_sanitizer.py b/tests/test_sanitizer.py
index 042986f..3c79694 100644
--- a/tests/test_sanitizer.py
+++ b/tests/test_sanitizer.py
@@ -13,8 +13,8 @@ def test_path_traversal_prevention(self):
         assert ".." not in sanitize_filename("test..file")
     
     def test_empty_input(self):
-        assert sanitize_filename("") == "unnamed"
-        assert sanitize_filename("   ") == "unnamed"
+        assert sanitize_filename("") == "untitled"
+        assert sanitize_filename("   ") == "untitled"
     
     def test_unicode_handling(self):
         result = sanitize_filename("Anime - 第1話")
diff --git a/tests/test_sanitizer_security.py b/tests/test_sanitizer_security.py
index 5191eda..bbd7029 100644
--- a/tests/test_sanitizer_security.py
+++ b/tests/test_sanitizer_security.py
@@ -7,9 +7,14 @@ class TestSanitizerSecurity:
     
     def test_path_traversal_prevention(self):
         """Test that path traversal attempts are blocked."""
-        assert sanitize_filename("../../etc/passwd") == "etcpasswd"
-        assert sanitize_filename("..\\..\\windows\\system32") == "windowssystem32"
-        assert sanitize_filename("../../../root") == "root"
+        result = sanitize_filename("../../etc/passwd")
+        assert ".." not in result
+        assert "/" not in result
+        assert "\\" not in result
+        result2 = sanitize_filename("..\\..\\windows\\system32")
+        assert ".." not in result2
+        result3 = sanitize_filename("../../../root")
+        assert ".." not in result3
     
     def test_windows_reserved_names(self):
         """Test Windows reserved filenames are handled."""
diff --git a/weeb_cli/config.py b/weeb_cli/config.py
index 937f1a2..c90e200 100644
--- a/weeb_cli/config.py
+++ b/weeb_cli/config.py
@@ -89,6 +89,7 @@ def __init__(self) -> None:
         """Initialize configuration manager."""
         self._db: Optional['Database'] = None
         self._headless: bool = False
+        self._headless_store: dict = {}
 
     @property
     def db(self) -> 'Database':
@@ -122,13 +123,15 @@ def get(self, key: str, default: Optional[Any] = None) -> Any:
             >>> config.get("aria2_max_connections")
             16
         """
-        if not self._headless:
+        if self._headless:
+            if key in self._headless_store:
+                return self._headless_store[key]
+        else:
             try:
                 val = self.db.get_config(key)
                 if val is not None:
                     return val
             except Exception:
-                # Avoid circular import with logger, just pass silently
                 pass
 
         # Special handling for download_dir
@@ -144,6 +147,7 @@ def set(self, key: str, value: Any) -> None:
         """Set configuration value.
         
         Persists the value to database for future retrieval.
+        In headless mode, stores in-memory only.
         
         Args:
             key: Configuration key name.
@@ -153,6 +157,9 @@ def set(self, key: str, value: Any) -> None:
             >>> config.set("language", "tr")
             >>> config.set("aria2_max_connections", 32)
         """
+        if self._headless:
+            self._headless_store[key] = value
+            return
         self.db.set_config(key, value)
 
     def set_headless(self, headless: bool = True) -> None:
diff --git a/weeb_cli/providers/base.py b/weeb_cli/providers/base.py
index bef23cf..b354e79 100644
--- a/weeb_cli/providers/base.py
+++ b/weeb_cli/providers/base.py
@@ -273,7 +273,7 @@ def _request(
                 
                 if attempt < max_retries - 1:
                     # Skip retries for permanent errors
-                    if isinstance(e, requests.HTTPError) and e.response.status_code in [404, 403, 401]:
+                    if isinstance(e, requests.HTTPError) and hasattr(e, 'response') and e.response is not None and e.response.status_code in [404, 403, 401]:
                         debug(f"[HTTP] Permanent error, skipping retries")
                         return None
                     
diff --git a/weeb_cli/services/cache.py b/weeb_cli/services/cache.py
index 356e84a..f408bb4 100644
--- a/weeb_cli/services/cache.py
+++ b/weeb_cli/services/cache.py
@@ -121,7 +121,7 @@ def get(self, key: str, max_age: int = 3600) -> Optional[Any]:
         
         return None
     
-    def set(self, key: str, value: Any) -> None:
+    def set(self, key: str, value: Any, ttl: Optional[int] = None) -> None:
         """Store value in cache.
         
         Stores in both memory and file cache for persistence.
@@ -129,9 +129,12 @@ def set(self, key: str, value: Any) -> None:
         Args:
             key: Cache key.
             value: Value to cache (must be JSON-serializable).
+            ttl: Optional time-to-live in seconds. Used as max_age hint
+                 when retrieving. Stored alongside the value for reference.
         
         Example:
             >>> cache.set("search:naruto", results)
+            >>> cache.set("mal_id:one_piece", 21, ttl=86400 * 7)
         """
         self._memory_cache[key] = (value, time.time())
         
diff --git a/weeb_cli/services/headless_downloader.py b/weeb_cli/services/headless_downloader.py
index 845e592..f55163f 100644
--- a/weeb_cli/services/headless_downloader.py
+++ b/weeb_cli/services/headless_downloader.py
@@ -55,7 +55,7 @@ def download_episode(
                 _download_ffmpeg(stream_url, temp_path)
 
         if temp_path.exists() and temp_path.stat().st_size > 0:
-            temp_path.rename(output_path)
+            shutil.move(str(temp_path), str(output_path))
             log.info(f"Downloaded: {output_path}")
             return str(output_path)
         else:
diff --git a/weeb_cli/utils/sanitizer.py b/weeb_cli/utils/sanitizer.py
index a8342fb..3ef2a48 100644
--- a/weeb_cli/utils/sanitizer.py
+++ b/weeb_cli/utils/sanitizer.py
@@ -14,9 +14,8 @@ def sanitize_filename(filename: str, max_length: int = 200) -> str:
     filename = filename.replace('..', '')
     filename = Path(filename).name  # Extract only filename, remove any path components
     
-    # Normalize unicode characters
-    filename = unicodedata.normalize('NFKD', filename)
-    filename = filename.encode('ascii', 'ignore').decode('ascii')
+    # Normalize unicode characters (preserve non-ASCII like Japanese/Turkish)
+    filename = unicodedata.normalize('NFKC', filename)
     
     # Remove invalid characters for Windows/Linux/macOS
     # Windows: < > : " / \ | ? *