Hi Xingcheng,
I have registered a long time ago and used to be able to see the Download page. However, when I tried to download it just now, the page does not show up. Could I be granted the access again?
As noted in the FAQ "How to make the best use of the Forum" (
http://forum.x3dna.org/faqs/how-to-make-the-best-use-of-the-forum/), private emails (gmail.com, yahoo.com, qq.com etc.) are no longer accepted on the 3DNA Forum. New registrations using private emails will be simply deleted. While previous such registrations (with posts), as in your case, are still kept, they do not have access to the download page any more.
Re-register on the 3DNA Forum using an identifiable (.edu) email, after
activation, you will see the download page.
Unactivated registrations will also been removed. I strive to keep this Forum spam-free and clean.
Hope this clarifies the issue.
Best regards,
Xiang-Jun