Just letting you know that when you try to upload a file greater than php will allow, Omeka doesn't seem to throw an error message.
For a while I was going a bit crazy because I was trying to upload a file and it simply wouldn't do anything. The page would just seem to refresh.
After changing the two php values "post_max_size" and "upload_max_filesize", I could then upload the largish file.
Perhaps for the next version of Omeka, an error message could be thrown when the filesize is too big.
We've tried to fix this problem in the past, but apparently it's a PHP problem. If the size of the POST exceeds the limits of those 2 ini values, it should trigger an error or at least put an error code into the $_FILES array, but it does neither of those things. As such we can't catch the error, nor can we manually check the size of the POST, since it overflows and resets to 0.
That said, it's possible that this has been fixed in a newer version of PHP, but I have no idea for certain. This has been a pretty annoying problem.