diff --git a/src/libslic3r/CSGMesh/PerformCSGMeshBooleans.hpp b/src/libslic3r/CSGMesh/PerformCSGMeshBooleans.hpp
index e98903378..7d0c13e71 100644
--- a/src/libslic3r/CSGMesh/PerformCSGMeshBooleans.hpp
+++ b/src/libslic3r/CSGMesh/PerformCSGMeshBooleans.hpp
@@ -275,14 +275,20 @@ It check_csgmesh_booleans(const Range<It> &csgrange, Visitor &&vfn)
         }
 
         try {
-            if (!m || MeshBoolean::cgal::empty(*m))
+            if (!m || MeshBoolean::cgal::empty(*m)) {
+                BOOST_LOG_TRIVIAL(info) << "check_csgmesh_booleans fails! mesh " << i << "/" << csgrange.size() << " is empty, cannot do boolean!";
                 return;
+            }
 
-            if (!MeshBoolean::cgal::does_bound_a_volume(*m))
+            if (!MeshBoolean::cgal::does_bound_a_volume(*m)) {
+                BOOST_LOG_TRIVIAL(info) << "check_csgmesh_booleans fails! mesh "<<i<<"/"<<csgrange.size()<<" does_bound_a_volume is false, cannot do boolean!";
                 return;
+            }
 
-            if (MeshBoolean::cgal::does_self_intersect(*m))
+            if (MeshBoolean::cgal::does_self_intersect(*m)) {
+                BOOST_LOG_TRIVIAL(info) << "check_csgmesh_booleans fails! mesh " << i << "/" << csgrange.size() << " does_self_intersect is true, cannot do boolean!";
                 return;
+            }
         }
         catch (...) { return; }
 
diff --git a/src/slic3r/GUI/GUI_Factories.cpp b/src/slic3r/GUI/GUI_Factories.cpp
index a710e72e5..26cd1c922 100644
--- a/src/slic3r/GUI/GUI_Factories.cpp
+++ b/src/slic3r/GUI/GUI_Factories.cpp
@@ -687,7 +687,7 @@ wxMenuItem* MenuFactory::append_menu_item_fix_through_netfabb(wxMenu* menu)
 
 void MenuFactory::append_menu_item_export_stl(wxMenu* menu, bool is_mulity_menu)
 {
-    append_menu_item(menu, wxID_ANY, _L("Export as one STL") + dots, "",
+    append_menu_item(menu, wxID_ANY, _L("Export as one STL"), "",
         [](wxCommandEvent&) { plater()->export_stl(false, true); }, "", nullptr,
         [is_mulity_menu]() {
             const Selection& selection = plater()->canvas3D()->get_selection();
diff --git a/src/slic3r/GUI/Plater.cpp b/src/slic3r/GUI/Plater.cpp
index 64d1a3357..251299f0c 100644
--- a/src/slic3r/GUI/Plater.cpp
+++ b/src/slic3r/GUI/Plater.cpp
@@ -11090,7 +11090,10 @@ void Plater::export_stl(bool extended, bool selection_only, bool multi_stls)
                 mesh.transform(volume->get_volume_transformation().get_matrix(), true);
             }
 
-            if (model_object->instances.size() == 1) mesh.translate(-model_object->origin_translation.cast<float>());
+            if (model_object->instances.size() == 1) {
+                //coconut: make the mesh's origin=(0,0,0). origin_translation is useless here.
+                mesh.align_to_origin();//translate(- model_object->origin_translation.cast<float>());
+            }
         }
         else if (selection.is_multiple_full_object() && !multi_stls) {
             const std::set<std::pair<int, int>>& instances_idxs = p->get_selection().get_selected_object_instances();