That's honestly a bit ridiculous. If you used Firefox, then you could click on the favicon (should be a soul dew icon to the left of the address bar) and hit More Information on the window that comes up.
Go to Media tab and you should be able to click on individual backsprites and use the "Save As" button.
Yes guys, I realize that I just told everybody how to bypass our very own "security" but that just goes to show you how freaking pointless it is.
Even this guy figured out how to rip them the hard way, I just told him an easier way to do it. :\
What do you mean, a shading fix? You're welcome to edit the sprites and if we like them better than what's up there now then we will certainly make the change.