Warner Bros. has responded to the issue on Twitter, stating that "some technical issues" caused the problem and that Skarlet will not be available until next week. Furthermore, the price of the costume pack will be corrected to £3.19 in the UK and €3.99 for the rest of Europe.
Meanwhile, in North America, users have been reporting that the Kombat Pass isn't functioning properly on Xbox Live. Once redeemed, Skarlet appears on Xbox Live for 1200 MS Points ($15) -- three times the standalone price -- instead of being free. We've contacted Warner Bros. about the issue.
In the meantime, Netherrealm Studios community manager Rigo Cortes has posted a workaround on Twitter, stating, "If Skarlet DLC is incorrectly showing up as 1200MS points in the game store, exit the game [and] go to the XBL store [through] the console."
Update: Warner Bros. has responded to Joystiq, noting that the problems reported by North American Xbox Live users have been "rectified." Those who ran into issues earlier this week should now find everything as it should be.