Please could somebody check the leader board in my free app is working correctly?

Hi
Just got my first Game Centre integrated app approved into the App Store. I seem to be unable to view things like the leader boards, and I think this is because I have various developer profiles on my iPhone. (Is this the case?)

Please would someone check this for me? The app is called 'Reaction Test Pro' and can be found here.

I just need to know that the leader board is actually being displayed and populated! If you are able to post a screenshot as well, that would be very much appreciated, though not necessary!

Thanks,

Sam

UPDATE: See below.

UPDATE: See below.

New version submitted that Apple claim fix the issue. No change for me (as using provisioned device). Again, please can somebody check this out on their iOS device?
Sam