Printing Levels (Layers) to PDF without Hierarchical Folder System

Hi All,

I'm having a problem when printing to PDF!

Using the pdf.pltcfg, I have turned on "Enable Optional Content" in Driver Properties to get it to create "Layers" in my PDF to match my DGN, no drama there.

My question is how do I get it to not create the Hierarchial folder system as shown below;

my preference is to get it to look like this;


Thanks in advance