Hi Quisling,
I don't know why the Prize is suddenly pdf only, it was definitely interactive last night but today it suddenly isn't. I think you're right though about the previous Maskarade puzzles being only being pdf.
Thanks again for your help with those three Listener clues, I only referred to 14d because I was so frustrated with myself for thinking "goodness" was the usual 2 letter word and completely missing the obvious the exclamation of surprise meaning. But, regards the other 2 clues, I was nowhere near parsing them so there was no point in beating myself up over it:-)
PS It's still interactive on the phone app.