use first map as default selection

src/components/Map/Drawer/ExportDrawer/ExportCompound/Submap/Submap.component.tsx

 import { ZERO } from '@/constants/common';
 import { useAppSelector } from '@/redux/hooks/useAppSelector';
 import { loadingModelsSelector, modelsDataSelector } from '@/redux/models/models.selectors';
-import { useContext } from 'react';
+import { useContext, useState } from 'react';
+import { CheckboxItem } from '@/components/Map/Drawer/ExportDrawer/CheckboxFilter/CheckboxFilter.types';
 import { CheckboxFilter } from '../../CheckboxFilter';
 import { CollapsibleSection } from '../../CollapsibleSection';
 import { ExportContext } from '../ExportCompound.context';
@@ -18,6 +19,16 @@ export const Submap = (): React.ReactNode => {
     label: name,
   }));
 
+  const options = useState<CheckboxItem[]>(mappedElementAnnotations);
+  if (
+    !isPending &&
+    currentSelectedModels.length === ZERO &&
+    options.length > ZERO &&
+    options[ZERO].length > ZERO
+  ) {
+    setModels([options[ZERO][ZERO]]);
+  }
+
   return (
     <CollapsibleSection title="Submap">
       {isPending && <p>Loading...</p>}