You can restore your xiaomi wcdma,follow this link
http://www.miui.it/forum/index.php?threads/guida-installazione-recovery-miui.2113/
For you sim i think you have a problem with you IMEI si restore your phone
Hi i receive my xiaomi red rice wcdma...I follow instruction for install miui multilanguage but i make a mistake: i flash gapps and after i've got some problezm: Usb debbuging doesn'work, Brownser too