diff --git a/classes/MLContent.php b/classes/MLContent.php
index eccfc0cc..75378a25 100644
--- a/classes/MLContent.php
+++ b/classes/MLContent.php
@@ -8,6 +8,8 @@
  */
 class MLContent extends MLCmsObject
 {
+    protected $allowedExtensions = ['htm', 'txt', 'md'];
+
     public static function findLocale($locale, $page)
     {
         if (!$page->exists) {
diff --git a/models/MessageImport.php b/models/MessageImport.php
index e7909ad8..3657727b 100644
--- a/models/MessageImport.php
+++ b/models/MessageImport.php
@@ -30,6 +30,7 @@ class MessageImport extends ImportModel
     public function importData($results, $sessionKey = null)
     {
         $codeName = MessageExport::CODE_COLUMN_NAME;
+        $defaultName = Message::DEFAULT_LOCALE;
 
         foreach ($results as $index => $result) {
             try {
@@ -44,8 +45,9 @@ public function importData($results, $sessionKey = null)
                     // Create empty array, if $message is new
                     $message->message_data = $message->message_data ?: [];
 
-                    if (!isset($message->message_data[Message::DEFAULT_LOCALE])) {
-                        $result[Message::DEFAULT_LOCALE] = $code;
+                    if (!isset($message->message_data[$defaultName])) {
+                        $default = (isset($result[$defaultName]) && !empty($result[$defaultName])) ? $result[$defaultName] : $code;
+                        $result[$defaultName] = $default;
                     }
 
                     $message->message_data = array_merge($message->message_data, $result);
diff --git a/tests/unit/behaviors/TranslatablePageTest.php b/tests/unit/behaviors/TranslatablePageTest.php
index e84efc8d..6220d627 100644
--- a/tests/unit/behaviors/TranslatablePageTest.php
+++ b/tests/unit/behaviors/TranslatablePageTest.php
@@ -22,13 +22,6 @@ public function setUp(): void
         $resolver = new Resolver(['theme1' => $datasource]);
         $resolver->setDefaultDatasource('theme1');
         Model::setDatasourceResolver($resolver);
-
-        TranslatablePage::extend(function($page) {
-            if (!$page->isClassExtendedWith('RainLab\Translate\Behaviors\TranslatablePage')) {
-                $page->addDynamicProperty('translatable', ['title']);
-                $page->extendClassWith('RainLab\Translate\Behaviors\TranslatablePage');
-            }
-        });
     }
 
     public function tearDown(): void
diff --git a/updates/builder_table_update_rainlab_translate_locales.php b/updates/builder_table_update_rainlab_translate_locales.php
index 8674f925..3468b177 100755
--- a/updates/builder_table_update_rainlab_translate_locales.php
+++ b/updates/builder_table_update_rainlab_translate_locales.php
@@ -1,30 +1,41 @@
-<?php namespace RainLab\Translate\Updates;
-
-use RainLab\Translate\Models\Locale;
-use Schema;
-use October\Rain\Database\Updates\Migration;
-
-class BuilderTableUpdateRainlabTranslateLocales extends Migration
-{
-    public function up()
-    {
-        Schema::table('rainlab_translate_locales', function($table)
-        {
-            $table->integer('sort_order')->default(0);
-        });
-
-        $locales = Locale::all();
-        foreach($locales as $locale) {
-            $locale->sort_order = $locale->id;
-            $locale->save();
-        }
-    }
-    
-    public function down()
-    {
-        Schema::table('rainlab_translate_locales', function($table)
-        {
-            $table->dropColumn('sort_order');
-        });
-    }
-}
\ No newline at end of file
+<?php namespace RainLab\Translate\Updates;
+
+use RainLab\Translate\Models\Locale;
+use Schema;
+use October\Rain\Database\Updates\Migration;
+
+class BuilderTableUpdateRainlabTranslateLocales extends Migration
+{
+    const TABLE_NAME = 'rainlab_translate_locales';
+
+    public function up()
+    {
+        if (!Schema::hasTable(self::TABLE_NAME)) {
+            return;
+        }
+
+        if (!Schema::hasColumn(self::TABLE_NAME, 'found')) {
+            Schema::table(self::TABLE_NAME, function($table)
+            {
+                $table->integer('sort_order')->default(0);
+            });
+        }
+
+        $locales = Locale::all();
+        foreach($locales as $locale) {
+            $locale->sort_order = $locale->id;
+            $locale->save();
+        }
+    }
+
+    public function down()
+    {
+        if (!Schema::hasTable(self::TABLE_NAME)) {
+            return;
+        }
+
+        if (Schema::hasColumn(self::TABLE_NAME, 'found')) {
+            Schema::dropColumn(['sort_order']);
+        }
+    }
+}
diff --git a/updates/update_messages_table.php b/updates/update_messages_table.php
index 37380276..7dbc713e 100644
--- a/updates/update_messages_table.php
+++ b/updates/update_messages_table.php
@@ -5,19 +5,30 @@
 
 class UpdateMessagesTable extends Migration
 {
+    const TABLE_NAME = 'rainlab_translate_messages';
+
     public function up()
     {
-        Schema::table('rainlab_translate_messages', function($table)
-        {
-            $table->boolean('found')->default(1);
-        });
+        if (!Schema::hasTable(self::TABLE_NAME)) {
+            return;
+        }
+
+        if (!Schema::hasColumn(self::TABLE_NAME, 'found')) {
+            Schema::table(self::TABLE_NAME, function($table)
+            {
+                $table->boolean('found')->default(1);
+            });
+        }
     }
 
     public function down()
     {
-        Schema::table('rainlab_translate_messages', function($table)
-        {
-            $table->dropColumn('found');
-        });
+        if (!Schema::hasTable(self::TABLE_NAME)) {
+            return;
+        }
+
+        if (Schema::hasColumn(self::TABLE_NAME, 'found')) {
+            Schema::dropColumn(['found']);
+        }
     }
-}
\ No newline at end of file
+}