Finally worked it out.
command should have been
"pdftk %i cat output c:\temp\output.pdf"

Export works great.

I am unable to export to pdf using the pages extension and PDFTK.
PDFTK is in the PATH, and I can access exe in cmd window.
When I run the create PDF, it opens a few CMD windows, but no PDF is created.
The command line is "pdftk %i cat c:\temp\output.pdf"
I am on win7 platform.
Thanks