Citrix support for Linux is currently (and has been for some time) completely attrocious, I have a previous post about this same issue. They do provide a deb and rpm version of Citrix reciever. The deb certainly has issues, and the rpm apparently does as well. Apart from the 32 bit and 64 bit packages being basically the same (ie the 64 bit version has 32 bit dependencies) the 64 bit package also lists requirements that no longer exist in most 64 bit distributions.

There are a number of how to's around on how to fix up the packages, they follow a similar set of steps as the ones I have listed here previously, so rather than oging through it again, here is a link to one of the better guides I have seen on how to set up : Citrix Receiver 13.0.0 on Ubuntu 14.04 Trusty

These steps work for me, apart from needing to link the browser plugin. ie. the citrix reciever package installed ok, but I had to then find my firefox plugins directory and link the citrix plugin manually ... ie

cd /usr/lib/firefox/browser/plugins
sudo ln -s /opt/Citrix/ICAClient/

After that I still had no luck, but changing the plugin to 'Always Activate' in firefox seemed to do the trick.