How to open one page of a multi-page file?
AddImageFile method of FRDocument object contains PageIndices parameter.
use the following C# code to open only the 2nd page of an image:
FRengine.IIntsCollection PageIndices = FREngine.CreateIntsCollection();
FRDocument.AddImageFile("MyImage.pdf", null, PageIndices);
Only the pages with numbers added in the PageIndices collection will be added to the document.