[McAroni]

No, the snipped excerpts coud not be resized. (but it would be a nice to have)

For inserting one page i would do the following:
Bring up the overlay for the song, press the pencil and go to files.
You have to bring two times your original file and one time the new to add file:

Your Sheet
Conductor Correction
Your sheet

for the first "your sheet" you set the page order until the new scanned page has to show up, and for the second "your sheet" those pages after the "conductors correction.

Your Sheet (page 1-10)
Conductor Correction (page 1)
Your sheet (page 11-20)


hope this is what you are looking for