[Schneckchen ^.^]

I want to start playing Simon 3D but I can't figure out how to save my game. I'm on the saving screen but when I enter a name for my savegame and press the enter button, instead of saving, the book turns to the next page of empty save slots.

Is this normal? Does anyone remember how to do this? It seems I've tried out every button to no avail. I'm using the GoG version.