from what ive seen so far, the hard core programming (c++ if not mistaken in this game and action-script for flash interface) are hidden and protected and cant be used by us users, but the XML, HTML stuff can be changed and you can also create new buttons for some of the UI stuff, for example, i have custom bottoms on top-right side of my screen to click and it directly opens the CLAIMS window, PETITION window, PERKS window, etc, instead of using the game's default ways (some of them still by chat command)
heres a screeny, the top right side buttons made by myself and configured by using the game XML files (radar is from Stonerune UI btw):
CLICK