You can use Danet Studio or Split XPS Merge to extract and merge pages from multiple XPS documents to create a new XPS document that contains the selected pages.
Here's a few step to split and merge an XPS documents using our software:
After a new XPS document is saved, you can see the new document in the Danet Creator, Danet Viewer, XPS Annotator or other XPS file viewer by double-clicking the file in Windows Explorer.
Note: For Danet Studio, this feature only available in Danet Studio Pro Edition.