diff --git a/src/slic3r/GUI/GUI_ObjectList.cpp b/src/slic3r/GUI/GUI_ObjectList.cpp
index d8d99fdf4..c8e656888 100644
--- a/src/slic3r/GUI/GUI_ObjectList.cpp
+++ b/src/slic3r/GUI/GUI_ObjectList.cpp
@@ -1415,13 +1415,18 @@ void ObjectList::update_opt_keys(t_config_option_keys& opt_keys)
 
 void ObjectList::load_subobject(ModelVolumeType type)
 {
-    auto item = GetSelection();
-    if (!item || m_objects_model->GetParent(item) != wxDataViewItem(0))
+    wxDataViewItem item = GetSelection();
+    // we can add volumes for Object or Instance
+    if (!item || !(m_objects_model->GetItemType(item)&(itObject|itInstance)))
         return;
-    int obj_idx = m_objects_model->GetIdByItem(item);
+    const int obj_idx = m_objects_model->GetObjectIdByItem(item);
 
     if (obj_idx < 0) return;
 
+    // Get object item, if Instance is selected
+    if (m_objects_model->GetItemType(item)&itInstance)
+        item = m_objects_model->GetItemById(obj_idx);
+
     std::vector<std::pair<wxString, bool>> volumes_info;
     load_part((*m_objects)[obj_idx], volumes_info, type);
 
diff --git a/src/slic3r/GUI/wxExtensions.cpp b/src/slic3r/GUI/wxExtensions.cpp
index 76ba853dc..06cf9b7d5 100644
--- a/src/slic3r/GUI/wxExtensions.cpp
+++ b/src/slic3r/GUI/wxExtensions.cpp
@@ -586,7 +586,7 @@ wxDataViewItem ObjectDataViewModel::AddVolumeChild( const wxDataViewItem &parent
 		ItemAdded(parent_item, child);
 
         root->m_volumes_cnt++;
-        if (insert_position > 0) insert_position++;
+        if (insert_position >= 0) insert_position++;
 	}
 
     const auto node = new ObjectDataViewModelNode(root, name, GetVolumeIcon(volume_type, has_errors), extruder_str, root->m_volumes_cnt);