I’ll definitely look into that, then – which OS are you using, and what specifically happens when you click the save button?
I'm on Mac OS Sequoia 15.4
Every time I clicked on save it would just make a buzzing sound and shake the screen slightly (the stantard reaction of rpg maker when you are attempting to use a feature that is no active) and all the slots would remain empty and dark.
And to confirm, had you double-clicked on a specific slot first to select it?
Yes I did.