I'm always on the lookout for more Lego Doctor Who animations, so thanks for sharing!
I love the music choice, it sets up a great atmosphere, and the slower pacing allows for a more thoughtful and suspenseful teaser.

None of the plot is spoiled, but not much is shown to intrigue or draw in viewers either, so you'll want to watch that balance in the future. Right now you're just running on 'Lego Doctor Who!' and 'Lego Cybermen!' Which works, but isn't as effective as it could be.

There are a few things that could be bettered, like the repetitious and looped smoke effect, as well as the post-production camera movement being a bit wild and starting/stopping at odd times. The sets look fantastic, a bit simple at times, but spacious and large. And you've picked one of the best TARDIS designs out there. What little animation I saw was slow and choppy, so hopefully it's a bit smoother in the final film.

I look forward to seeing the final film, so be sure to share it on here!