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Your link goes to a blank page, for me. But I think I understand enough from your description, at least to offer some potentially helpful info. Oh wait, I see it! I expected it to be in the middle of the page.
Well anyway, first, do Ctrl + A to select everything. Then Edit menu > Duplicate (or command bar button). Then use Down Arrow on keyboard to move the duplicate straight down, until it's in the position you need. Since the arrow is so small, you might need to use Alt + arrow, to move in much smaller steps (depending on the zoom level). Or, if you want to move it to be precisely top of duplicate touching bottom of original, you can use the Y value on the control bar.
It sounds like you might also want to change the page size. File menu > Document Properties > Page tab > Page size > Custom size.
