Update - I received an email within 10 minutes saying my download was now activated. Everything working properly now. Hope this helps anyone having this problem in the future.

I just purchased an item through paypal, and a search brought me to this thread. My payment went through and I received a payment confirmation from Renderosity. However, when I go to download, it says "download pending". I have emailed customer service and I will update this post when/if the issue is resolved.