diff --git a/src/MyFirstUDRKit.cpp b/src/MyFirstUDRKit.cpp
index c07fd8b..bbece68 100644
--- a/src/MyFirstUDRKit.cpp
+++ b/src/MyFirstUDRKit.cpp
@@ -24,13 +24,13 @@
  */
 
 
-#define FB_UDR_STATUS_TYPE ::Firebird::ThrowStatusWrapper
 
-
-//#include <ibase.h>
-//#include <firebird/UdrCppEngine.h>
 #include "MyFirstUDRKit.h"
 
+#include <ibase.h>
+#include <firebird/UdrCppEngine.h>
+#include "UdrCppTemplates.h"
+
 #include <cassert>
 #include <cstdio>
 #include <cstdlib>
@@ -68,7 +68,6 @@
 
 #include <limits>
 
-using namespace std;
 using namespace Firebird;
 
 
@@ -185,7 +184,7 @@ FB_UDR_MESSAGE(OutMessage,
 
 AutoRelease<IAttachment> att;
 AutoRelease<ITransaction> tra;
-AutoRelease<IBlob> Blob;
+AutoRelease<IBlob> blob;
 
 FB_UDR_EXECUTE_FUNCTION
 {
@@ -206,12 +205,9 @@ FB_UDR_EXECUTE_FUNCTION
 
 		att.reset(context->getAttachment(status));
 		tra.reset(context->getTransaction(status));
+		blob.reset(att->openBlob(status, tra, &in->ablob, 0, nullptr));
 
-		// This is wrong - the calling application should pass in a blob handle
-		//AutoRelease<IBlob> Blob(att->openBlob(status, tra, &in->ablob, 0, nullptr));
-		Blob.reset(att->openBlob(status, tra, &in->ablob, 0, nullptr));
-
-		if (Blob == nullptr) {
+		if (blob == nullptr) {
 			out->result = -1;
 			return;
 		}
@@ -222,7 +218,9 @@ FB_UDR_EXECUTE_FUNCTION
 		while  ( FileReader.good() ) {
 			FileReader.read( Buffer.data(), Buffer.size() );
 			DataSize = FileReader.gcount();
-			Blob->putSegment( status, DataSize, Buffer.data() );
+			// fail seems to be here...
+			// Probably need to declare buffer differently.
+			blob->putSegment( status, DataSize, Buffer.data() );
 			out->result += DataSize;
 			// Perhaps test for badbit here?
 		}
@@ -230,16 +228,17 @@ FB_UDR_EXECUTE_FUNCTION
 			// What to do?
 			out->resultNull = FB_TRUE;
 			// What do we do with the partially written blob? Is cancel enough?
-			Blob->cancel( status );
+			blob->cancel( status );
 			// Should we reset result to 0?
 
 		}
-			Blob->close( status );
-			Blob->release();
+			blob->close( status );
+			blob->release();
 			Buffer.clear();
 	}
 	catch (...)
 	{
+		// This generates an unrecognised C++ exception, which is insufficient.
 		throw std::runtime_error("Error writing stream to BLOB.");
 	}
 
@@ -291,7 +290,7 @@ FB_UDR_EXECUTE_FUNCTION
 	 * DOC NOTE - We do not test for existence of the file here!
 	 */
 
-	fstream File ( in->afilename.str , fstream::out | fstream::binary | fstream::app );
+	std::fstream File ( in->afilename.str , std::fstream::out | std::fstream::binary | std::fstream::app );
 	if (! File.is_open()) {
 		out->result = -2;
 		return;
@@ -305,7 +304,7 @@ FB_UDR_EXECUTE_FUNCTION
 	}
 
 
-	vector<char> Buffer (MaxSegmentSize, 0);
+	std::vector<char> Buffer (MaxSegmentSize, 0);
 
 	unsigned BytesRead = 0;