Black and White reversed

I'm using QuickPDF Library TQuickPDF0721 in Delphi 7 to display about 90,000 different .pdf files, all of which are composed of only two colors: black text on a white background.

Using Adobe, all the files display correctly. However using QuickPDF Library, about half of the .pdfs display normally and the other half display in reversed black and white (like a photo negative).

Is there some switch in QuickPDF Library that I can set so that it displays in black and white correctly?

Thanks in advance for any help you can provide.

To solve this bug, is it possible for me to just download the most recent version and install it?  Does my license cover this upgrade from 7.21 to 7.23?   Can I just install over top of the older version or do I have to remove the older version?  Will my unlock key work with the newly downloaded version?  Keep in mind that I purchased the product many months ago, in anticipation that it would work when I eventually needed it, and my project only now has progressed to the point that I need it, and now this "black / white reversal" has prevented me from using the product at all.   7.21 is defective to the point that it is unusable, so I think I deserve a free bug fix update.