With advanced filename you can add a zero before the day number if you want one.

• Please activate advanced filename in the PDF tab.
• Configure the rules for the PDF filename. Ex: <Sheet Number>_0<Day>.<Month>.<Year>
• Save the configuration
• Publish the selected sheets

The latest version of Docuflow is 2.8.

Is ist possible to get Dates mit two Letters like 01 for January?

Docuflow 2.7 only writes Dates without a zero.