why would modifying something, esp. when asking not be legal
you havent put your name under it, so he can't complain
in my opinion the SMF themes were just meant to be modded...
most of the originals suck xD
untill you change them
and besides, SMF provides the function to change the CSS, wich comes out to the same as inverting the images (making the theme look better)
just gotta love smf