Games, particularly new ones, can often have rules fixes that are quickly found as the relatively small amount of players that'd tried it originally grows to several thousand with the game's release. Well, Beyond the Gates of Antares hasn't been around for too long yet, but there's been some things that've been updated. Well, that new version is available as a .pdf from the Warlord Games webshop.
Of course, some of you just like rulebooks in .pdf format anyway. This one is full of internal links, so if you need to cross-reference anything, you don't have to manually flip through all the pages. It also incorporates all of Rick Priestley's errata so it's the most up-to-date version yet of the rules.