If you are using CSVtoHistory script then you can change timestamp before exporting to t6. Actually I just realised I do this with Dukascopy data:

Code
	
        int i;
	for(i=0; i<Records; i++)
		dataSet(1,i,0,dataVar(1,i,0)+(1/(24.0*60))); // Add a minute to change from open bar dates to close bar dates