Hello,
We are on 2.2.5+ (Build: 20120920) and we experience the same issue.
the swf file appears to be loaded but it is not displayed....
the only problem is that we are talking about Teachers, not students experiencing the problem.
I enabled the multimedia filter,
I went to Site Administration>Security>Site policies and checked the "enable trusted content" box.
I also went to Site Administration>Users>Permissions>Define roles and allowed Trust Submitted content moodle/site:trustcontent for teacher role (well it was already allowed).
however we still see the issue.
would you know if this is actually more than just a students´ restriction or something is going on here...
Thanks
Imbu