I was trying a variety of different approaches, so in the code pasted here it actually uses "Application.Windows(nb.Name).Activate" instead - but the outcome is the same.

As for why jumping between workbooks, it is because changes are being made to both in the course of the code that has been omitted - it takes about 5-10secs to process everything, during which time the original workbook is displayed. Only at the end, once the export has completed, should the new workbook be visible and activated.

As I say, the code works perfectly in 2010.