I had the same problem - I ordered four items and the DS4 Auto-Fit (which is free, but still). The 4 downloadables were stuck in Pending status from my downloads page, and apparently a serial number to input for the Auto-Fit should appear on my serial numbers page, but so far has not. I’m still waiting for a serial number, I did open a ticket.
However, I managed to download the items still pending - I clicked on the reset link, and the item were then available for downloading.
Still, while there are a few things I would like to purchase, I dare not, especially seeing this is a major and widespread problem. I’ll go spend my money over at Renderosity instead this weekend.
IMHO - this whole new upgrade really blows, including the item pages in the shop. One thing I miss very much is the link to Accessories which I no longer see. All this “new and improved” which to me is a complete disappointment, and you can’t even purchase without fail. :(