I changed my CSC to XSG and installed the exact same versions of framework and Pay app as you.Samsung Pay 2.7.03 (apk from apkmirror)
Framework 2.7.51
Yes US version is properly working.
It doesn't let me go past the Start screen
Update: Installed 2.7.14 which I extracted from a US S8, it let me get past the start screen but it now registers as a UAE Pay app.
I don't know what the case was when you registered but there's no way I'm able to register it as the US version of Pay
Last edited: