I guess some people had problems with the pose on the wallpaper/posters made from the summer event? JP side has a thread about it and rep responded.

Original Thread Link: http://goo.gl/EVr7O

Quote Originally Posted by Triairy View Post
こんばんは。
Good Evening,

こちら状況を確認し修正の対応を行いましたので、あらためて壁紙のダウンロードをお試しください。
なお、壁紙のダウンロードは9/5（月）までになっておりますのでお早めにどうぞ！
We checked the situation and fixed the problem, please try the wallpaper download once again. Please note the wall paper download will be till 9/5 (Monday) [US Sunday 09/04] so please do it quickly!

ご報告ありがとうございました！
Thanks for reporting!