i had the same issue when purchasing. However, i still did not receive a mail containing a link / key. How long did it take for you? Paypal confirmed the transaction and i am used to instant responses from humblebundle.
I’m having the same problems. I pre-ordered the game through the humble widget and paypal sent me an e-mail that I payed it, but I also got the linking problem en didn’t receive a download/key.
re-sender did actually work, the link was credited to my paypal mail address and not my humble mail address. It seems being logged in did not link the purchase.