The ability to customize a tool does not seem like something worth more than a short notice, but after using it for a while, you would not want to live without it anymore. Photoshop has a similar feature, but RealWorld Designer takes it to the next level.
There used to be an extension for RealWorld Icon Editor 2006.1 that allowed thumbnails in open file dialogs and in Windows Explorer for U3D and R3I files. It was nifty but incompatible with later versions (because it required a lot of entries in registry and that was especially hard to do under Vista). Today, the thumbnail extractor is back in it has all the bells and whistles that you would expect from a RW tool…
Buttons are ugly. Even buttons with nice images on them can become ugly. Especially if they are small and you have to click them every few seconds. Future versions of RW tools will utilize mouse gestures to fight this problem. And once you get used to them, there is no going back.
It is boring to do the same thing over and over again. Or isn’t it? … Anyway, in case of photo editing, repetition gets boring pretty quick and many editors solve this problem with a scripting subsystem. And so will RealWorld Photos.