Index: image_gallery/code/ImageGalleryManager.php
===================================================================
--- image_gallery/code/ImageGalleryManager.php	(revision 511)
+++ image_gallery/code/ImageGalleryManager.php	(working copy)
@@ -238,4 +238,4 @@
 }


-?>
\ No newline at end of file
+?>
Index: image_gallery/code/ImageGalleryPage.php
===================================================================
--- image_gallery/code/ImageGalleryPage.php	(revision 511)
+++ image_gallery/code/ImageGalleryPage.php	(working copy)
@@ -53,10 +53,10 @@
 	}

 	function onBeforeWrite() {
-    parent::onBeforeWrite();
-    if( $this->ID )
-    	$this->RootFolder()->Title = $this->Title;
-   }
+	    parent::onBeforeWrite();
+	    if( $this->ID )
+		    $this->RootFolder()->Title = $this->Title;
+    }

 	function onAfterWrite()
 	{
@@ -70,14 +70,23 @@
 		$this->RootFolder()->delete();
 	}
 	*/
+
+	function generateRootFolderName() {
+		$prefix = Object::has_extension('SiteTree', 'Translatable')?
+			str_replace('_', '-', $this->Locale) . '-': '';
+		// Combining $this->Link() with the Locale will make name collisions almost
+		// impossible, the result is then hashed to ensure that it fits in File->Filename.
+		return md5("{$prefix}{$this->Link()}");
+	}
+
 	function checkFolder() {
 		if( ! $this->RootFolderID ) {
 			$galleries = Folder::findOrMake('image-gallery');
 			$galleries->Title = 'Image Gallery';
 			$galleries->write();
-			$folder = Folder::findOrMake('image-gallery/' . $this->URLSegment);
+			$folder = Folder::findOrMake("image-gallery/{$this->generateRootFolderName()}");
 			$folder->Title = $this->Title;
-			$folder->setName($this->Title);
+			$folder->setName($this->generateRootFolderName());
 			$folder->write();

 			$this->RootFolderID = $folder->ID;
@@ -87,7 +96,7 @@
 			FormResponse::add( "\$( 'Form_EditForm' ).getPageFromServer( $this->ID );" );
 		}
 		else {
-			$this->RootFolder()->setName($this->Title);
+			$this->RootFolder()->setName($this->generateRootFolderName());
 			$this->RootFolder()->write();
 		}

@@ -219,11 +228,11 @@

 	private static function get_default_ui()
 	{
-    $classes = ClassInfo::subclassesFor("ImageGalleryUI");
-    foreach($classes as $class) {
-      if($class != "ImageGalleryUI") return $class;
-    }
-    return false;
+	    $classes = ClassInfo::subclassesFor("ImageGalleryUI");
+	    foreach($classes as $class) {
+	      if($class != "ImageGalleryUI") return $class;
+	    }
+	    return false;
 	}

 	public function GalleryUI()
@@ -266,7 +275,7 @@

 		if($items === null)
 			$items = $this->Items($limit);
-	  $this->includeUI();
+	    $this->includeUI();
 		if( $items ) {
 			foreach( $items as $item ) {
 				if($this->Square)
@@ -287,7 +296,7 @@
 					$item->setUI($this->UI);
 				}
 			}
-	  	return $this->UI->updateItems($items);
+			return $this->UI->updateItems($items);
 		}
 		return false;
 	}
@@ -333,43 +342,42 @@

 	public function init()
 	{
-
 		parent::init();
 		Requirements::themedCSS('ImageGallery');
 	}

 	public function index()
 	{
-			if($this->SingleAlbumView())
-				return $this->renderWith(array($this->getModelClass().'_album','Page'));
-			return $this->renderWith(array('ImageGalleryPage','Page'));
+		if($this->SingleAlbumView())
+			return $this->renderWith(array($this->getModelClass().'_album','Page'));
+		return $this->renderWith(array('ImageGalleryPage','Page'));
 	}

 	private function getModelClass()
 	{
-	  return str_replace("_Controller","",$this->class);
+		return str_replace("_Controller","",$this->class);
 	}

 	private function getModel()
 	{
-    return DataObject::get_by_id($this->getModelClass(),$this->ID);
+		return DataObject::get_by_id($this->getModelClass(),$this->ID);
 	}


 	protected function adjacentAlbum($dir)
-  {
-      $t = $dir == "next" ? ">" : "<";
-      $sort = $dir == "next" ? "ASC" : "DESC";
-      return DataObject::get_one(
-         $this->albumClass,
-         "ImageGalleryPageID = {$this->ID} AND SortOrder $t {$this->CurrentAlbum()->SortOrder}",
-         false,
-         "SortOrder $sort"
-      );
-  }
-
-  public function NextAlbum()
 	{
+		$t = $dir == "next" ? ">" : "<";
+		$sort = $dir == "next" ? "ASC" : "DESC";
+		return DataObject::get_one(
+			$this->albumClass,
+			"ImageGalleryPageID = {$this->ID} AND SortOrder $t {$this->CurrentAlbum()->SortOrder}",
+			false,
+			"SortOrder $sort"
+		);
+	}
+
+	public function NextAlbum()
+	{
 		return $this->adjacentAlbum("next");
 	}

@@ -391,4 +399,4 @@

 }

-?>
\ No newline at end of file
+?>
Index: image_gallery/code/ImageGalleryItem.php
===================================================================
--- image_gallery/code/ImageGalleryItem.php	(revision 511)
+++ image_gallery/code/ImageGalleryItem.php	(working copy)
@@ -38,11 +38,19 @@
 	{
 		parent::onBeforeWrite();

-		if($image = $this->Image()) {
+		$image = $this->Image();
+		if($image->ID) {
 			if(isset($_POST['AlbumID']) && $album = DataObject::get_by_id("ImageGalleryAlbum", $_POST['AlbumID'])) {
 				$image->setField("ParentID",$album->FolderID);
 				$image->write();
 			}
+		} else if(!$image->ID && $this->ImageID) {
+			// Image is not a valid ImageGalleryImage, but we have an ImageID, if that
+			// ImageID references a real image we should change it into an ImageGalleryImage.
+			if ($image = DataObject::get_by_id('Image', $this->ImageID)) {
+			    $image = $image->newClassInstance('ImageGalleryImage');
+			    $image->write();
+			}
 		}
 	}

@@ -88,4 +96,4 @@
 	{
 		return Permission::check(self::$delete_permission);
 	}
-}
\ No newline at end of file
+}