Call Save As DXF in startcommand

I am looking for a way to call the "save as dxf" command in a CATvba macro to generate dxf files in a batch process form CATParts, (with the Generative Sheetmetal Workbench).  The DXF command button from the "Manufacturing Preparation" toolbar button works fine for single CATParts.  My problem is bypassing the user interaction that required in the save as window, accpeting the defaults and sending the "SAVE" key.

Did you get any solution on this? here I'm also developing an utility to convert sheetmetal part into dxf file.

Please help me on this if you have done already anything.

Thanks in advance.