diff --git a/pcbnew/dialogs/dialog_footprint_checker.cpp b/pcbnew/dialogs/dialog_footprint_checker.cpp
index 1b10f7511f..967fb02473 100644
--- a/pcbnew/dialogs/dialog_footprint_checker.cpp
+++ b/pcbnew/dialogs/dialog_footprint_checker.cpp
@@ -177,10 +177,13 @@ void DIALOG_FOOTPRINT_CHECKER::OnSelectItem( wxDataViewEvent& aEvent )
 
     if( node && item )
     {
-        PCB_LAYER_ID             principalLayer = item->GetLayerSet().Seq()[0];
+        PCB_LAYER_ID             principalLayer = UNDEFINED_LAYER;
         LSET                     violationLayers;
         std::shared_ptr<RC_ITEM> rc_item = node->m_RcItem;
 
+        if( item->GetLayerSet().count() > 0 )
+            principalLayer = item->GetLayerSet().Seq().front();
+
         if( rc_item->GetErrorCode() == DRCE_MALFORMED_COURTYARD )
         {
             BOARD_ITEM* a = board->GetItem( rc_item->GetMainItemID() );
diff --git a/pcbnew/drc/drc_test_provider_disallow.cpp b/pcbnew/drc/drc_test_provider_disallow.cpp
index 25ab38395e..46addefbd9 100644
--- a/pcbnew/drc/drc_test_provider_disallow.cpp
+++ b/pcbnew/drc/drc_test_provider_disallow.cpp
@@ -201,21 +201,25 @@ bool DRC_TEST_PROVIDER_DISALLOW::Run()
     auto checkDisallow =
             [&]( BOARD_ITEM* item )
             {
-                auto constraint = m_drcEngine->EvalRules( DISALLOW_CONSTRAINT, item, nullptr,
-                                                          UNDEFINED_LAYER );
+                DRC_CONSTRAINT constraint = m_drcEngine->EvalRules( DISALLOW_CONSTRAINT, item,
+                                                                    nullptr, UNDEFINED_LAYER );
 
                 if( constraint.m_DisallowFlags && constraint.GetSeverity() != RPT_SEVERITY_IGNORE )
                 {
                     std::shared_ptr<DRC_ITEM> drcItem = DRC_ITEM::Create( DRCE_ALLOWED_ITEMS );
 
-                    m_msg.Printf( drcItem->GetErrorText() + wxS( " (%s)" ),
-                                  constraint.GetName() );
+                    m_msg.Printf( drcItem->GetErrorText() + wxS( " (%s)" ), constraint.GetName() );
 
                     drcItem->SetErrorMessage( m_msg );
                     drcItem->SetItems( item );
                     drcItem->SetViolatingRule( constraint.GetParentRule() );
 
-                    reportViolation( drcItem, item->GetPosition(), item->GetLayerSet().Seq()[0] );
+                    PCB_LAYER_ID   layer = UNDEFINED_LAYER;
+
+                    if( item->GetLayerSet().count() )
+                        layer = item->GetLayerSet().Seq().front();
+
+                    reportViolation( drcItem, item->GetPosition(), layer );
                 }
             };
 
diff --git a/pcbnew/pcb_painter.cpp b/pcbnew/pcb_painter.cpp
index 8a8020d950..80038e5a57 100644
--- a/pcbnew/pcb_painter.cpp
+++ b/pcbnew/pcb_painter.cpp
@@ -421,11 +421,13 @@ bool PCB_PAINTER::Draw( const VIEW_ITEM* aItem, int aLayer )
                 if( IsPcbLayer( aLayer ) && parentFP->GetPrivateLayers().test( aLayer ) )
                     return false;
             }
-            else
+            else if( item->GetLayerSet().count() == 1 )
             {
                 // For single-layer objects, exclude all layers including ancillary layers
                 // such as holes, netnames, etc.
-                if( parentFP->GetPrivateLayers().test( item->GetLayerSet().Seq()[0] ) )
+                PCB_LAYER_ID singleLayer = item->GetLayerSet().Seq()[0];
+
+                if( parentFP->GetPrivateLayers().test( singleLayer ) )
                     return false;
             }
         }
diff --git a/pcbnew/tools/board_inspection_tool.cpp b/pcbnew/tools/board_inspection_tool.cpp
index c36c3fb8d7..e8167fd614 100644
--- a/pcbnew/tools/board_inspection_tool.cpp
+++ b/pcbnew/tools/board_inspection_tool.cpp
@@ -388,9 +388,11 @@ int BOARD_INSPECTION_TOOL::InspectClearance( const TOOL_EVENT& aEvent )
 
     if( copperIntersection.any() && zone && pad && zone->GetNetCode() == pad->GetNetCode() )
     {
-        PCB_LAYER_ID layer = active;
+        PCB_LAYER_ID layer = UNDEFINED_LAYER;
 
-        if( !zone->IsOnLayer( active ) )
+        if( zone->IsOnLayer( active ) )
+            layer = active;
+        else if( zone->GetLayerSet().count() > 0 )
             layer = zone->GetLayerSet().Seq().front();
 
         r = m_inspectClearanceDialog->AddPage( _( "Zone" ) );
diff --git a/pcbnew/zone.cpp b/pcbnew/zone.cpp
index 5b6df50928..0e4e4994ed 100644
--- a/pcbnew/zone.cpp
+++ b/pcbnew/zone.cpp
@@ -884,7 +884,7 @@ void ZONE::HatchBorder()
     int  hatch_line_len = m_borderHatchPitch;
 
     // To have a better look, give a slope depending on the layer
-    int     layer = GetLayerSet().Seq()[0];
+    int     layer = GetFirstLayer();
     int     slope_flag = (layer & 1) ? 1 : -1;  // 1 or -1
     double  slope = 0.707106 * slope_flag;      // 45 degrees slope
     int     max_a, min_a;