Hey Mate, I've just flashed this to my B7610 UK version, and it works, United Kingdom regional settings and all. However one feature I hate about WM 6.5.3 is applications don't close when pressing "X" button even though its enabled in Samsung Settings.
I'm gonna try X2 TaskManager see if it will help. Otherwise I'll be going back to huzheyi's Customised Rom.
I think this needs to be enabled in the windows settings, which is default not visible in the start menu.
To make it visible go to: HKLM\Security\Shell\StartInfo open HideSettings and change the value to 0
To open the registry from your phone use CeRegEditor and connect your phone to your pc.