Tried to view media and I see gobble gook!
That was a little hard to decipher, but it is, in fact, a bug inadvertently introduced into version 3.3.12. I will raise it, with the fix, in the bugs section properly, but for now can you copy the file contained in the zip folder attached here to your server (replacing the existing ‘admin_media.php’ file in your kiwitrees root folder).
I don’t believe it will actually fix your basic problem, but it will help us investigate it better. Let me know when you have installed that file, and I’ll take another look at your broader media issues.