Much older SDK version had functions PXCp_ImageGetFromPage & PXCp_GetDocImageAsXCPage and that was very easy to browse which images where attached to a page. (Used it to extract the single image generated by most scanners in order to look for some specific QR codes inside). Is this still possibl...

Much older versions of the SDK had functions like:

PXCp_OptimizeFonts, PXCp_OptimizeRemoveNamedDests, PXCp_OptimizeStreamCompression

By what are they replaced in the current PDF-XChange Core API SDK?
Are they part of another SDK?

The page https://www.pdf-xchange.com/pdf-creation-and-manipulation-sdks-comparison-chart says that PDF-XChange Core API SDK has features to scan directly to PDF (Twain & WIA). What part of the SDK does indeed support that? I don't find anything with the word Scan or Twain through the search box ...