You really need to use the blorbtool script, otherwise each time you release in I7 you’re going to lose the images. Or if you re-order some source text then the images might get numbered differently and then you’ll be showing the wrong image.
The script is fairly straightforward to run; after each time you click Release in I7, also run a script that executes:
python blorbtool.py "Your Story.materials/Release/Your Story.gblorb" giload "Your Story.materials/Release/interpreter" interpreter
The quotes are important when you have spaces in your story name. This assumes you’re running it from the I7 Projects folder; if you’ve put the scripts elsewhere then you’ll have to amend the paths accordingly. (I usually run it from inside the materials folder, so I don’t include that part of the path.)