I have a working solution for batch saving as PDF for all your sheets in one file. My way creates all the PDF files without interference named as the sheets are incl. date and whatever you like to add to the name. I use Quickeys and a plugin made by Jonker & Wu (VW trainer and programmer) in the Netherlands. This is really saving me a lot of time. Works fine although Quickeys will cost you 90 USD and the program is not very functional otherwise.
Hope this will do. Unbelievable btw that Nemethek is not providing this basic functionally.
