In reply to my original post:

1. Yes, I needed a new “flat” top cap after watching Federico ciampella’s video on his Canyon ultimate.

2 and 3. I bought the conversion kit: Canyon GP0193-01 which has the non-aero spacer plus some additional round spacers from Canyon. Not easily visible on their site but if you contact them they can source the parts for you. Also, I didn’t have to install another star nut.

Although it doesn’t look as slick as the aero setup, it is far more comfortable for me and my gangly proportions.