I am new to theme modding and don't know where to start. I have the Darkmatter Subspace theme that I want to edit because the moron who designed it somehow thought leaving the white explorer background was a good idea even though it clashes with absolutely everything. I've been trying to use Windows Style Builder, but whenever I try to save my edits and apply the theme, nothing happens and the theme is broken. I just want to edit a few things. Anyone know where I should start looking and why Windows Style Builder will not create a theme that can actually be applied?

P.S. Yes I've already modified my system to accept other non-microsoft visual styles.