Hi, I work with a lot of sewing patterns that are saved as PDF files. I used to use Nuance Power PDF and when I saved the PDFs to Explorer, I could choose the thumbnail option in the lower right and it would use the first page of the pdf file (which was an image of patterns in that file) as the thumbnail. Since I switched to PDF Architect the thumbnail is just the Architect logo. I switched the file association for PDFs to Nuance and it shows the first page as the thumbnail. I switch back to PDF Architect and it just shows the icon above.
which version of PDF Architect you've installed?