Since you have a rule for all css, js and images, those attached to the tickets and news and wikis will not be downloadable. You will receive 404 error, since these files are NOT in /public/ folder (their url is like http://domain.com/attachments/download/12345/filename.png).
To fix this fast, one can just disable the section with
location ~* ^.+.(?:css|js|jpe?g|gif|htc|ico|png|html)$
...
Since you have a rule for all css, js and images, those attached to the tickets and news and wikis will not be downloadable. You will receive 404 error, since these files are NOT in /public/ folder (their url is like http://domain.com/attachments/download/12345/filename.png).
To fix this fast, one can just disable the section with
location ~* ^.+.(?:css|js|jpe?g|gif|htc|ico|png|html)$
...