Just by curiosity (since now I manually solved my problem!), why do you use the "SET" function to create reference values?

I followed exactly the method as described in the link to minimize errors since I'm experienced with programming, but not with the use of word fields. And in this method, I didn't saw the "SET" function. I only saw there was a difference between the field coding of the last page (reference value) and of all other pages: "NUMPAGES" was used instead of "PAGE".

The other question is: how to indicate to the table of contents to list the output of these field codes instead of the raw page number of each files?

Best!