Unfortunately there is another interpretation of the information on the web site: The TWAIN driver is only available for Windows. Not every scanner manufacturer delivers TWAIN drivers for the Mac. So it looks like you are out of luck as far as scanning directly into Acrobat goes.
You can however use the Image Capture application on the Mac and scan your documents (just make sure that you scan to PDF). You would then in a second step open the scanned document in Acrobat and use the features to optimize scanned documents (Tools>Document Processing>Optimize Scanned PDF).
Karl Heinz Kremer
PDF Acrobatics Without a Net
PDF Software Development, Training and More...
http://www.khkonsulting.com