Cleatless

Thank you - I knew it had to be simples!

My first go with a RAW file, .NEF, from an approved camera. It opened in Develop Persona, I got fantastic results from adjustments, and I love the workspace. But I can't find the 'commit' button, so the program won't allow me to leave the persona for any other one, nor can I save my adjustments. Well and truly a stuck beginner. What am I overlooking (probably the obvious)?