Regex Filename replace on profile printing


i'm trouble with regex in pdfcreator so someone may help me to fix my problem (prob only in my head) :wink:
So i will change the printing Titel to the new TextString. So i spend more time to good things in live and not into delete manual on every pdf creating.

My Programm send the Filename like:

2013-Rechnung1 - RE2000005 (Rechnung I) 10121 Firma Company Name GmbH Surname Name - Street. 5, ZIP Code Place.pdf

but the Filename should only RE(7-Digits).pdf The hole other Information about Company and everything else should removed.

So first question is this possible the work with regex and replace in PDFCreator on the fly by printing. Second question how should the regex look like?