If memory serves, on the Two Towers soundtrack, "Isengard Unleashed" is one of the last songs (track 17?), but in the movie, Isengard is "unleashed" as the Uruk's make their way towards Helm's Deep.
So, maybe the track listings aren't supposed to be in pure order?
Yeah, the TTT soundtrack was definitely out of order, but he was doing it in 'themes' I guess.
I don't care; I'll adjust. ;o)