The preferences edition dialog is a prototype. You may as well edit your resources/medialib.prop file in a mere text editor. Preferences properties allows to customize a lot of things. They will be reviewed in the 0.3 final version in detail. For example, you may try to set the "medialib.icons.directory" property to "small_gui" if you would prefer smaller icons. If your preferences are messed up, just remove the file [medialib-install]/resources/medialib.prop.
