You don't need a macro, you can do this with the stationary pad. Make sure the stationary pad is empty before you begin and then at the field for the title, use the {variable} for the field you want to enter there. Then apply the stationary to any of the files you like to set the title for in this way.
Hope this helps,
Hayo
P.S. Make sure you test this on a couple of sample images first.