I didn't know LibreOffice, but just looked at it, and I guess it COULD be possible as you suggest, assuming LO outputs to PP standards.
Make sure all the elements are SAVED as you go along.
Alternatively, do the text, pictures, and other elements in a Windows program (Word, or similar), so that all the items are there, and Saved.
Then, could she take to school on a memory stick, and do the final editing and assembly of elements at school?
You don't say what Yr group DD is, but one of the biggest PP errors is to make it too 'fancy' with twirling text etc. Clean, accurate, well balanced, with text large enough to read if projected, not too many fonts (ideally two or three), suitable pictures, graphics, and consistent colours throughout looks more professional, than gimmicks and 'fireworks' that make the viewer dizzy!
(But maybe kids like a bit of 'fireworks' and think looking 'professional' isn't cool!)