Good news! Update for the app has allowed my account to be linked successfully.
I have noticed the 'Navigation Functionality' problem mentioned earlier but I think you can rectify this quicker by turning the pad off and on (saves you rebooting the app).
FEEDBACK - I'm finding subscribed videos stop at the 50 mark when selecting the 'All Videos' function. Additionally, when using the search function to locate any video, it maxes at 100 (although the number may be 10,000 total, for example).