I have accidentally performed a factory reset on my BT Homehub and in so doing have deleted all of my downloaded movies. (Including all of the Marvel movies I had bought for my children... I'm not popular!!)
Resetting your Homehub wouldn't remove any downloads from anywhere. I can see you have purchased a number of movies on BT TV - these are still on your account, and can be watched/downloaded on all the same platforms as before. What device specifically are you trying to watch on @KMcG?
Edit: I should have said, there's known issue in the apps on Android and iOS devices at the moment that nothing can currently be downloaded. We're working with Microsoft on this, and will fix it as soon as possible.