I've eventually solved this problem using an AutoIt script (see http://www.autoitscript.com/autoit3/). I had never used this (free) tool before, it took just a couple of hours for me to learn its basics and have the script up and running. I recommend it to those having similar needs. Some knowledge of BASIC language required.
I have some 700 NWC files that need to be converted to pdf. I suppose I have to print them using cutepdf or a similar virtual print driver.
This number of files definitely requires some kind of automation. I've found some suggestion in a very old topic here, which appear not to be a fully automated solution. Maybe some better solution is now available. Can anybody help?