Thanks for the reply, I must say I'm surprised; I thought the save function in AGS was always present, and if you didn't specifically disallow its F5 shortcut it would still be there. I re-downloaded AGS and I see that the empty game template doesn't include that, what a strange choice. Not a good one, I'm afraid. I'd thought you'd specifically gone there and removed the function.
Well, things are quite unclear when we're beginners, so whatever happened, happened, and that's the end of it. Thank you very much for the clarification.