diff --git a/web_interface/blueprints/api_v3.py b/web_interface/blueprints/api_v3.py
index 3a3b2574..bfa86ddb 100644
--- a/web_interface/blueprints/api_v3.py
+++ b/web_interface/blueprints/api_v3.py
@@ -1682,7 +1682,13 @@ def execute_system_action():
             })
         elif action == 'install_plugin_requirements':
             active_pm = getattr(api_v3, 'plugin_manager', None)
-            plugins_dir = Path(active_pm.plugins_dir) if active_pm else PROJECT_ROOT / 'plugin-repos'
+            if active_pm:
+                plugins_dir = Path(active_pm.plugins_dir)
+            else:
+                _cm = getattr(api_v3, 'config_manager', None)
+                _cfg = _cm.load_config() if _cm else {}
+                _dir_name = _cfg.get('plugin_system', {}).get('plugins_directory', 'plugin-repos')
+                plugins_dir = Path(_dir_name) if os.path.isabs(_dir_name) else PROJECT_ROOT / _dir_name
             results = []
             if plugins_dir.exists():
                 for p in sorted(plugins_dir.iterdir()):
@@ -4630,27 +4636,34 @@ def save_plugin_config():
                         continue
                     pt = ps.get('type')
                     val = cfg[k]
-                    if pt == 'array' and isinstance(val, dict):
-                        keys = list(val.keys())
-                        if keys and all(str(x).isdigit() for x in keys):
-                            sorted_keys = sorted(keys, key=lambda x: int(str(x)))
-                            items_schema = ps.get('items', {})
-                            item_type = items_schema.get('type')
-                            arr = [val[sk] for sk in sorted_keys]
-                            if item_type in ('integer', 'number'):
-                                converted = []
-                                for v in arr:
-                                    if isinstance(v, str):
-                                        try:
-                                            converted.append(int(v) if item_type == 'integer' else float(v))
-                                        except (ValueError, TypeError):
+                    if pt == 'array':
+                        items_schema = ps.get('items', {})
+                        item_type = items_schema.get('type')
+                        if isinstance(val, dict):
+                            keys = list(val.keys())
+                            if keys and all(str(x).isdigit() for x in keys):
+                                sorted_keys = sorted(keys, key=lambda x: int(str(x)))
+                                arr = [val[sk] for sk in sorted_keys]
+                                if item_type in ('integer', 'number'):
+                                    converted = []
+                                    for v in arr:
+                                        if isinstance(v, str):
+                                            try:
+                                                converted.append(int(v) if item_type == 'integer' else float(v))
+                                            except (ValueError, TypeError):
+                                                converted.append(v)
+                                        else:
                                             converted.append(v)
-                                    else:
-                                        converted.append(v)
-                                arr = converted
-                            cfg[k] = arr
-                        elif not keys:
-                            cfg[k] = []
+                                    arr = converted
+                                cfg[k] = arr
+                            elif not keys:
+                                cfg[k] = []
+                        # Recurse into each element when items are objects with properties,
+                        # covering both freshly-converted and already-list values.
+                        if item_type == 'object' and 'properties' in items_schema:
+                            for elem in (cfg[k] if isinstance(cfg[k], list) else []):
+                                if isinstance(elem, dict):
+                                    _fix_json_arrays(elem, items_schema['properties'])
                     elif pt == 'object' and 'properties' in ps and isinstance(val, dict):
                         _fix_json_arrays(val, ps['properties'])
             _fix_json_arrays(plugin_config, schema['properties'])
diff --git a/web_interface/templates/v3/partials/tools.html b/web_interface/templates/v3/partials/tools.html
index 0fcbeeee..3e249988 100644
--- a/web_interface/templates/v3/partials/tools.html
+++ b/web_interface/templates/v3/partials/tools.html
@@ -229,7 +229,14 @@
             headers: {'Content-Type': 'application/json'},
             body: JSON.stringify({action})
         })
-        .then(r => r.json())
+        .then(r => {
+            if (!r.ok) {
+                return r.json()
+                    .then(d => Promise.reject(new Error(d.message || `HTTP ${r.status}`)))
+                    .catch(() => Promise.reject(new Error(`HTTP ${r.status}`)));
+            }
+            return r.json();
+        })
         .then(data => {
             const ok = data.status === 'success';
             showResult(