Convert CDR to transparent PNG using the file converter macro

So I have hundreds of CDR files that I would like to convert to transparent PNGs, I have tried using the file converter macro but have been unable to find an option for transparent background. All the PNGs will come out with a solid white background...

Now I know that I can just export these files individually to PNGs with transparent backgrounds, but that would take forever. Can someone please help?

Thanks,