Open a document (or multiple documents) where the pages need to be re-arranged (or merged).
In the Tools-menu, open Switchboard.
Go to the Pages-section.
Select the "Organize pages" and click "Execute" to open the work-window.
This is how your document will be presented. The pages are laid out in their current order. You can show them as Thumbnails, page numbers or both.
Multiple opened documents will all show up on their own line, making it easy to select the correct page from the correct document.
Select and drag to the new document to alter the page-positions.
Once all the pages have been re-arranged in either your existing document or in a new-one, you click on Apply to generate the document again.
When merging multiple documents together or changing pages by provided correction-pages, the software will give you a clear overview of which page came from which document, by underlining it with the same color as the filename is underlined with. So, you can either keep the existing name of the original document, and only change the correction-pages in it, or you can create a new document which will combine the files from the original and the corrected pages.
You will see that a second tab appeared when you dragged the pages into a new document. When you re-positioned the pages within the same document, they will show the new order immediately.
The only thing left now is to save your document.