Practically you need only access to Google Play Market. All GApps are stored where (at your choice ). The way to install Google Play in your case is: extract file Phonesky.apk from zip arhive and launch it (inside phone, indeed). So you will have access to Google Play Market. Enjoy!... tell me the right way to install ngapps?
I'd already tried fix Permissions.Its in the ROM . zip... so try to fix permissions in CWM... or look into system/app for MIUIGallery.apk and set permissions to rw-r--r--