CREO pdf export OUTPUT problems

I have been using Creo 3.0 (M070) for the past 1 year. I usually encounter problems while exporting to pdf version from Creo. When i export my drawing to pdf through "Quick Export" option, the drawing views look ugly. The outline of the drawing view is too thick and due to that the outline of a view is unreadable.
The Situation is " Suppose if i have two square box on one over the other with a thickness of 1mm, the output of the pdf version is so dark that the 1mm thick is unable to find" .

PTC Community indicated to use hidden config option which is "intf_pdf_use_adaptive_linestyle to no". But i am finding difficult to create a new config.pro file in Creo and saving the same.

Can anyone help me " What is my actual problem?" . Will the above config,pro file help me find a solution?. If so, can anyone help me on how too create a new config.pro file?

I saw the videos in PTC Community on Creating Config.pro file but that doesn't show clearly on How to add a new configuration?

Please help!

Thanks in advance.

Regards,
Tamil.