It would appear that somehow during the recent rehash of the forum a mistake has been made that has resulted in connections to the online DOCshop going awry. In short, there are duplicated files where there should not be, and this has led to re-directs to the shop resulting in a blank page. I was unaware of this until this evening, and will be endeavouring to get it sorted and normal service resuned tonight.
Sorry. 
Problem fixed. 
There was some sort of file duplication that was causing an error, but how it happened is a mystery to me.