Well, I gues chronologically "Movement" comes after "Still", so that makes sense. There was a quote from Barney where he said something along the lines of New Order were once part of the factory empire, but no more, hence "Republic". Over on A.N Other forum, someone claimed that "Low-Life" was a comment on both the band's fanbase and the Order themselves (the band becoming increasingly cocky and obnoxious circa 84-85); "Brotherhood" was also claimed to be a sly nod to the band-fan relationship, as well as the tight-knit band collective. "Substance" is obviously about drugs, plus it's better than "New Order: The Singles". "Technique" I guess is about the band fine-tuning their skills (again remember Wilson quote from TV about them learining to make singles about three singles in, but only perfected the art of LPs with this one). As for "PC&L", I dunno, but if you swapped it with "Republic" it'd make more sense. "Get Ready"? Fuck knows. Probably just the obvious.
But, of course, they play their cards very close to their chest, so this is (as ever) just idle speculation......