Not having any problems with the Creation Engine currently. Appreciate some people are. Have built a huge settlement with the "size" glitch, not crashed once:
[WARNING: Rude Word Commonly Used in the UK and Australia in the Flashing Billboard. If you are under 16 Please do not click]
http://giphy.com/gifs/xTk9ZAf4kfPz3WPWOk
The only real problems with the engine I have are petty and they are mostly related to how Havok works within it.
Edit: My hardware is comprised of a 3770k CPU overclocked, GTX980 and 16 GB of RAM.