Hi,
I've worked on that issue for quite a while today and made an extensive patch to the smart search plugin to handle this properly.
The issue was that the elements were not reindexed when saving them from the interface.
So once you had indexed them once, the changes you would made to the products would be ignored by the smart search.
So what you need to do is this:
- download again the install package of the 4.4.0 on our website and install it on yours
- click on the "index" button of the smart search component to resynchronize the products
Then, it should hopefully work fine.