diff --git a/src/SHMessage/SHAPE.fr b/src/SHMessage/SHAPE.fr
index 02aa95080d..1913c58085 100755
--- a/src/SHMessage/SHAPE.fr
+++ b/src/SHMessage/SHAPE.fr
@@ -25,19 +25,19 @@
 ! ------------------------------------------------------------------------------
 ! Messages for sequence of operators
 ! 
-.Sequence.MSG0
+.SP.Sequence.Info.Seq
 Sequence d'operateurs: %s
 !
-.Sequence.MSG5
+.SP.Sequence.Info.Operator
 Operateur %d/%d: %s
 !
-.Sequence.MSG1
+.SP.Sequence.Error.NoOp
 Error: Operator %s is not found
 !
-.Sequence.MSG2
+.SP.Sequence.Error.Except
 Error: Operator %s failed with exception %s
 !
-.Sequence.MSG3
+.SP.Sequence.Warn.NoSeq
 Warning: Shape Processing: sequence not defined for %s
 !
 ! ------------------------------------------------------------------------------
diff --git a/src/SHMessage/SHAPE.us b/src/SHMessage/SHAPE.us
index 1c708c6fa1..2eaf53ba6b 100755
--- a/src/SHMessage/SHAPE.us
+++ b/src/SHMessage/SHAPE.us
@@ -26,20 +26,20 @@
 ! ------------------------------------------------------------------------------
 ! Messages for sequence of operators
 ! 
-.Sequence.MSG0
-Info: Sequence of operators: %s
+.SP.Sequence.Info.Seq
+Info: Shape Processing: Sequence of operators: %s
 !
-.Sequence.MSG5
-Error: Operator %d/%d: %s
+.SP.Sequence.Info.Operator
+Info: Shape Processing: Operator %d/%d: %s
 !
-.Sequence.MSG1
-Error: Operator %s is not found
+.SP.Sequence.Error.NoOp
+Error: Shape Processing: Operator %s is not found
 !
-.Sequence.MSG2
-Error: Operator %s failed with exception %s
+.SP.Sequence.Error.Except
+Error: Shape Processing: Operator %s failed with exception %s
 !
-.Sequence.MSG3
-Warning: Shape Processing: sequence not defined for %s
+.SP.Sequence.Warn.NoSeq
+Warning: Shape Processing: Sequence not defined for %s, nothing to do
 !
 ! ------------------------------------------------------------------------------
 ! Messages for printing results of shape processing
diff --git a/src/ShapeProcess/ShapeProcess.cxx b/src/ShapeProcess/ShapeProcess.cxx
index 2e7830b34f..5eba8fa031 100644
--- a/src/ShapeProcess/ShapeProcess.cxx
+++ b/src/ShapeProcess/ShapeProcess.cxx
@@ -81,6 +81,10 @@ Standard_Boolean ShapeProcess::Perform (const Handle(ShapeProcess_Context)& cont
 #ifdef OCCT_DEBUG
     cout << "Error: ShapeProcess_Performer::Perform: sequence not defined for " << seq << endl;
 #endif
+    if ( context->TraceLevel() >0 ) {
+      Message_Msg SMSG3 ("SP.Sequence.Warn.NoSeq"); // Sequence %s not found
+      context->Messenger()->Send (SMSG3 << seq, Message_Warning);
+    }
     context->UnSetScope();
     return Standard_False;
   }
@@ -95,7 +99,7 @@ Standard_Boolean ShapeProcess::Perform (const Handle(ShapeProcess_Context)& cont
   
   // put a message
   if ( context->TraceLevel() >=2 ) {
-    Message_Msg SMSG0 ("Sequence.MSG0"); //Sequence of operators: %s
+    Message_Msg SMSG0 ("SP.Sequence.Info.Seq"); //Sequence of operators: %s
     TCollection_AsciiString Seq;
     for ( Standard_Integer i1=1; i1 <= sequenceOfOperators.Length(); i1++ ) {
       if (i1 > 1) Seq += ",";
@@ -106,11 +110,12 @@ Standard_Boolean ShapeProcess::Perform (const Handle(ShapeProcess_Context)& cont
   }
 
   // iterate on operators in the sequence
+  Standard_Boolean isDone = Standard_False;
   for (i=1; i<=sequenceOfOperators.Length(); i++) {
     oper = sequenceOfOperators.Value(i);
     
     if ( context->TraceLevel() >=2 ) {
-      Message_Msg SMSG5 ("Sequence.MSG5"); //Operator %d/%d: %s
+      Message_Msg SMSG5 ("SP.Sequence.Info.Operator"); //Operator %d/%d: %s
       SMSG5 << i << sequenceOfOperators.Length() << oper.ToCString();
       context->Messenger()->Send (SMSG5, Message_Alarm);
     }
@@ -118,7 +123,7 @@ Standard_Boolean ShapeProcess::Perform (const Handle(ShapeProcess_Context)& cont
     Handle(ShapeProcess_Operator) op;
     if ( ! ShapeProcess::FindOperator ( oper.ToCString(), op ) ) {
       if ( context->TraceLevel() >0 ) {
-        Message_Msg SMSG1 ("Sequence.MSG1"); //Operator %s not found
+        Message_Msg SMSG1 ("SP.Sequence.Error.NoOp"); //Operator %s not found
         context->Messenger()->Send (SMSG1 << oper, Message_Alarm);
       }
       continue;
@@ -127,11 +132,11 @@ Standard_Boolean ShapeProcess::Perform (const Handle(ShapeProcess_Context)& cont
     context->SetScope ( oper.ToCString() );
     try {
       OCC_CATCH_SIGNALS
-      if ( !op->Perform(context) )
-        return Standard_False;
+      if ( op->Perform(context) )
+        isDone = Standard_True;
     }
     catch (Standard_Failure) {
-      Message_Msg SMSG2 ("Sequence.MSG2"); //Operator %s failed with exception %s
+      Message_Msg SMSG2 ("SP.Sequence.Error.Except"); //Operator %s failed with exception %s
       SMSG2 << oper << Standard_Failure::Caught()->GetMessageString();
       context->Messenger()->Send (SMSG2, Message_Alarm);
     }
@@ -139,5 +144,5 @@ Standard_Boolean ShapeProcess::Perform (const Handle(ShapeProcess_Context)& cont
   }
   
   context->UnSetScope();
-  return Standard_True;
+  return isDone;
 }
diff --git a/src/XSAlgo/XSAlgo_AlgoContainer.cxx b/src/XSAlgo/XSAlgo_AlgoContainer.cxx
index 1e00efe53a..3ee0d3acb4 100644
--- a/src/XSAlgo/XSAlgo_AlgoContainer.cxx
+++ b/src/XSAlgo/XSAlgo_AlgoContainer.cxx
@@ -129,7 +129,7 @@ TopoDS_Shape XSAlgo_AlgoContainer::ProcessShape (const TopoDS_Shape& shape,
       time++;
     }
 #endif
-    // if FromSTEP or FromIGES, do default ShapeFix
+    // if reading, do default ShapeFix
     if ( ! strncmp ( pseq, "read.", 5 ) ) {
       try {
         OCC_CATCH_SIGNALS
@@ -157,11 +157,8 @@ TopoDS_Shape XSAlgo_AlgoContainer::ProcessShape (const TopoDS_Shape& shape,
       }  
       return context->Result();
     }
-    // if ToSTEP or ToIGES, define sequence of DirectFaces
-    else if ( ! strcmp ( pseq, "write.step.sequence" ) ) {
-      rsc->SetResource ( str.ToCString(), "DirectFaces" );
-    }
-    else if ( ! strcmp ( pseq, "write.iges.sequence" ) ) {
+    // for writing, define default sequence of DirectFaces
+    else if ( ! strncmp ( pseq, "write.", 6 ) ) {
       rsc->SetResource ( str.ToCString(), "DirectFaces" );
     }
   }
@@ -171,7 +168,7 @@ TopoDS_Shape XSAlgo_AlgoContainer::ProcessShape (const TopoDS_Shape& shape,
   rsc->SetResource ( "Runtime.MaxTolerance", maxTol );
 
   if ( !ShapeProcess::Perform(context, seq) )
-    return TopoDS_Shape(); // Null shape
+    return shape; // return original shape
 
   return context->Result();
 }