Well the Citrix installation is pretty easy, just download the files @ Citrix , extract and run (preferably as superuser/root) the ./setupwfc file.
When it comes to Citrix & Linux, the certificates are at least for me the most common error. You get an error message like this
You have chosen not to trust " XX ", the issuer of the server's security certificate (SSL error 61).
in my case:
You have chosen not to trust "PositiveSSL CA", the issuer of the server's security certificate (SSL error 61).
Which ofcourse makes sense, as long as the root certificate is not present, it will not accept this SSL host. To make life easy and be lazy, just copy all the certificates from Mozilla, just because the most common certificates are present there. Copy the Mozilla cert to the Citrix directory
sudo cp /usr/share/ca-certificates/mozilla/* /usr/lib/ICAClient/keystore/cacerts/
Which will provide you with the most common certificates. Of course you can grab your own root certificates at your provider, the choice is up to you