You are going to make an awesome grandpa (if not already). One of the coolest stories I've heard. We have a convert boys!....took a few years, but he saw the light. Lol. Good to hear. You'll be fine. BTW, I have no knowledge of this bike. Only thing I've heard about BMW's (from my dad...ex motorcycle crasher...now retired), is that if you crash them you'll probably need to replace the engine because the heads hit the ground. Question: is the seating position as aggressive as the Jap bikes?
My first trackday was on my 1098S in April at CMP and from one trackday noob to another, you're going to have an absolute blast! Could I have a smaller bike more suited to learning? Yes of course, but I don't. Check your ego in at the gates, listen to your group leader, remind yourself to relax the death grip, trust your tires and have fun learning and meeting other enthusiasts. The first session is used to get you comfortable with the track, it's like a tour of the track and is generally slow. By the third session the pace will quicken and you'll work on braking from higher speeds and may even put your knee down for the first time. By the 4th session your group leader has a good idea who is comfortable with the track/speed and their bike and in my experience waved us ahead after 2 laps. My biggest challenge? I had to keep reminding myself that it's not a race(over and over again)! See you at the track!