GB store is well and truly useless. Multiple attempts to login followed by long wait then "server error" message. Once actually logged in pages taking ages to load (varying from several minute minutes to never) and throwing server errors or time-outs far more often than loading a page.
This has been the situation since I first tried to buy X3 on early Saturday afternoon (UK time).
Even if I could get as far as a shopping cart I'm unwilling to put in any payment details as if the transaction times out at any stage that's just loads more hassle.
Giving up.