Linux Mint Forums

If you have done apt-get update or the same in Synaptic and don't get newer versions it means that there are none. Then the never versions in Daryna (Gutsy) are not available for Cassandra/Celena (Feisty) - they are not in those repositories and you can't use Darynas repos in Celena

A) I don't know if there's newer versions of the applications for Celena - did not check, just answered the basic question
B) You can't use the repository of one version in another, unfortunately there are changes made in the code so you'll mess things up
Some applications will work in more than one version, you could find a .deb file that installs nicely, but that's another question and it's by no means certain.

most distros are backwards compatible, but to try and use programs coded for newer kernels, on an older one, it's like trying to Play a DVD on a CD player, you can use a CD on a DVD player, but the other way around.