We love seeing Unity refugees in 
That’s not to say we want anyone to stop using Unity - both Unity and UE are excellent engines with their own strengths. We just want to be simple across the board.
Direct manipulation of UMG widgets is not possible right now because we’re missing the ability to reference widgets outside of the blueprint that owns them, but this functionality will be in 4.6, as Darnell said. However, I’ve come up with an interim solution using the messaging system that will remain forward compatible. There will be UMG-specific tweening operations in the near future, but you can tween them now if you need to using the messaging system and those tweens will continue to work forever. Or at least until I break something.
I guffed the last two videos (trying to piece together clips instead of one contiguous video has resulted in two different irrelevant clips getting mixed) and I am re-rendering them now. If you’d like to start tweening your UMG stuff, the (quite long, sorry) videos on messaging and iTProxy. Part 1 is ready to . Part 2 is mostly complete but is missing the ending and the video on iTProxy needs to be completely re-rendered. Look for them within the hour.