Unchecked Checkbox disappears after flattening

Did this recently start happening you started processing different types of PDF files or started using a different version of Quick PDF Library?

I was mistaken.  The real solution had to do with the way the PDF forms were being created.  The forms are first created in MS Word.  These documents are what we have to submit for approval.  Once approved, the typesetter was setting the font color on all checkboxes in the Word document to white (basically making them hidden).  The document was then converted to PDF and form fields were added over the top of the hidden checkboxes.  Upon flattenting the PDF document, the white checkboxes (maybe...sure seems like) were being placed over the formfield checkboxes.  Once we figured out to delete the checkboxes from the Word document before converting to PDF, the problem went away.  For some reason, the Word checkbox does not convert to a formfield as required according to our typesetter.