Adding winning bid to user's cart only works intermittently

Hi there, first of all thanks for a truly awesome module. This auction module runs rings around the others on offer.

But I've been pulling my hair out for over two weeks now trying to get around a very annoying problem.
When any given auction has ended, the winning bid is hardly ever getting added to that user's cart automatically. I can manually open the node and that triggers the action, but from what I've read, it should happen automatically, I gather from being picked up during the next Cron run.

I'm not a programmer so I'm hesitant to tamper with the code. I've wanted to hide the "Add to cart" button so I set the "field_product" as "hidden" from view. And it seems that any change to the "auction_timeout" field immediately stuffs up the automated winning bid to cart routine. Even attempting to relocate this field for display seems to stuff it up.

If there's a bug in that automated routine, I guess the only alternative would be to use rules / components to do it but every attempt I've made at this just gives me a headache :)

Any advice would be greatly appreciated.