Use Flex 4.5.1 and when add icons to the button is so curve effect of scaling.
Prompt how to make a proportional scaling icons?
<s:Button width="100%" height="50" label="Create new map" click="button3_clickHandler(event)"
fontSize="22" icon="@Embed('icons/001-folder.png')">
try to create custom skin for button and do the same in commitProperties