diff --git a/src/app/components/IECPage.tsx b/src/app/components/IECPage.tsx
index 69008b3..c99cd61 100644
--- a/src/app/components/IECPage.tsx
+++ b/src/app/components/IECPage.tsx
@@ -24,6 +24,18 @@ export default function IECPage({ config, setConfig }: IECPageProps) {
 
   const iec = config.iec || {};
 
+  const boolDirEntries = Object.entries(iec.directory || {}).filter(([, v]) => v === 0 || v === 1);
+  const isCompatMode   = boolDirEntries.length > 0 && boolDirEntries.every(([, v]) => v === 0);
+
+  const setAllDirBools = (val: 0 | 1) => {
+    const newConfig = JSON.parse(JSON.stringify(config));
+    const dir = newConfig.iec?.directory ?? {};
+    for (const k of Object.keys(dir)) {
+      if (dir[k] === 0 || dir[k] === 1) dir[k] = val;
+    }
+    setConfig(newConfig);
+  };
+
   return (
     <div className="p-4 space-y-4">
       <h2 className="text-sm text-neutral-500 flex items-center gap-2"><Cable className="w-4 h-4" /> IEC Settings</h2>
@@ -172,30 +184,39 @@ export default function IECPage({ config, setConfig }: IECPageProps) {
       <h2 className="text-sm text-neutral-500 pt-4 flex items-center gap-2"><List className="w-4 h-4" /> Directory Enhancements</h2>
 
       <div className="bg-white border border-neutral-200 rounded-lg divide-y divide-neutral-200">
+        {/* CBM Directory Compatibility Mode */}
+        <div className="p-4 flex items-center justify-between bg-neutral-50">
+          <div>
+            <div className="text-sm font-medium text-neutral-700">CBM Directory Compatibility</div>
+            <div className="text-xs text-neutral-400 mt-0.5">Disables all directory enhancements</div>
+          </div>
+          <button
+            onClick={() => setAllDirBools(isCompatMode ? 1 : 0)}
+            className={`relative w-12 h-6 rounded-full transition-colors ${isCompatMode ? 'bg-blue-600' : 'bg-neutral-300'}`}
+          >
+            <div className={`absolute top-0.5 w-5 h-5 bg-white rounded-full transition-transform ${isCompatMode ? 'translate-x-6' : 'translate-x-0.5'}`} />
+          </button>
+        </div>
+
         {Object.entries(iec.directory || {}).map(([key, value]) => (
-          <div key={key} className="p-4 flex items-center justify-between">
+          <div key={key} className={`p-4 flex items-center justify-between transition-opacity ${isCompatMode ? 'opacity-40' : ''}`}>
             <label className="text-sm text-neutral-500">
               {key.replace(/_/g, ' ').replace(/\b\w/g, l => l.toUpperCase())}
             </label>
-            {typeof value === 'number' ? (
+            {value === 0 || value === 1 ? (
               <button
-                onClick={() => updateSetting(['iec', 'directory', key], value ? 0 : 1)}
-                className={`relative w-12 h-6 rounded-full transition-colors ${
-                  value ? 'bg-blue-600' : 'bg-neutral-300'
-                }`}
+                onClick={() => { if (!isCompatMode) updateSetting(['iec', 'directory', key], value ? 0 : 1); }}
+                className={`relative w-12 h-6 rounded-full transition-colors ${value ? 'bg-blue-600' : 'bg-neutral-300'} ${isCompatMode ? 'cursor-not-allowed' : ''}`}
               >
-                <div
-                  className={`absolute top-0.5 w-5 h-5 bg-white rounded-full transition-transform ${
-                    value ? 'translate-x-6' : 'translate-x-0.5'
-                  }`}
-                />
+                <div className={`absolute top-0.5 w-5 h-5 bg-white rounded-full transition-transform ${value ? 'translate-x-6' : 'translate-x-0.5'}`} />
               </button>
             ) : (
               <input
                 type="number"
                 value={value}
+                disabled={isCompatMode}
                 onChange={(e) => updateSetting(['iec', 'directory', key], parseInt(e.target.value))}
-                className="w-24 px-3 py-1 border border-neutral-300 rounded-lg text-right"
+                className="w-24 px-3 py-1 border border-neutral-300 rounded-lg text-right disabled:cursor-not-allowed"
               />
             )}
           </div>
diff --git a/src/imports/config.json b/src/imports/config.json
index 1314663..cec571a 100644
--- a/src/imports/config.json
+++ b/src/imports/config.json
@@ -95,11 +95,11 @@
       "nfo_header": 1,
       "hidden_dirs": 1,
       "hidden_files": 1,
+      "long_filenames": 1,
       "extension_colon": 1,
       "date_time": 1,
       "load_address": 1,
       "sys_address": 1,
-      "entry_length": 16,
       "footer_bytes": 1
     },
     "fastloaders": {