Well, for the background link, I think that the webpage has a problem, You can see all the internal links just under -Download- link, They aren't good too. In the next part of the page, some links have the same URL structure and work.
I can't explain why, because if the link doesn't exists, it ought to display an error page.
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Mail : alain [dot] aupeix [at] wanadoo [dot] fr
Ubuntu 12.04 - Gramps 3.4.9 - Harbour 3.2.0 - Hwgui 2.20-3 - K-Meleon 76.0 rc