I've been using the Genereate>Image Assets for a while and love it. The issue I have when you have a folder of layers with effects on them that's named to resize, it doesn't freeze the layers before creating the assets.
...Well after trying to create an example test image, the problem doesn't exist, but it still exists in my original template PSD I use for all my DVD menus. So it must be some switch somewhere that I'm missing.
Here's my example images below. See how it's not working on the second set at the bottom. Here are the source files also.