Chromecast with remote voice HD was not as easy to setup as claimed. Firstly required Google Home app update on iOS mobile which needs V14 to load, thanks Google I am stuck on V12!. Connected to Hitachi 22" and could not setup volume, power and inputs even though 16 possible codes. Then I read a review of the TV that said it was identical to Bush model, selected Bush and successful set up immediately. Suprised BBC iplayer is not included on Google TV especially as all the programmes are listed only to get message to cast from phone. Not everyone can afford to have the latest tech and these gizmo designers need to give that some thought.
I'm sorry to hear about your experience but, good to hear that you're able now to set up the buttons on your Chromecast Voice Remote.
With regards to BBC, we’re working with BBC to bring the BBC iPlayer app to Chromecast with Google TV (HD). In the meantime, you can cast BBC content from the mobile app. Check this support article to see how you can cast video from Chromecast-enabled apps to your TV.