Sorted! Bike now booked onto the 10:45 train from Inverness. Phoned up the number for internet bookings and spoke to a very nice woman who booked the bike on the train for me. Just need to print out the ticket at the station. FYI she did say that if you book through
thetrainline.com you need to phone up to book the bike. Seems a bit daft that you can’t just do it online at the same time as you book your seat, but took all of three minutes on the phone two of which were listening to recorded messages.