Cannot display default layout on Xibo player - Ubuntu 12.04

Hi everybody,
I need your help. I am a newbie to Ubuntu and I am working on Ubuntu 12.04 with Xibo.
I have installed the Xibo server and everything seems to be ok; same thing for the client (client can connect to the server), except for the fact that only the splash screen is displayed on the player; the default layout doesn’t work and I have tried to download and add also some other layouts, but nothing happens.
If I press ‘i’ on the player the output is the following.

Required files: green tick
Get file: 0
Schedule: green tick
Register display: green tick
Log: green tick
Stats: grey circle

When I launch the player from the terminal I get this error
[3683:3691:4607839961:ERROR:process_singleton_linux.cc(264)] Failed to create /opt/xibo/pyclient/client/python/.berkelium/SingletonLock: File exists

Server and client are on the same machine. I’m just trying to test is everything could be ok before moving to install the client on another machine.
I have tried different potential solutions, read all topics related to mine, but I don’t know what to do more.
Thank you,

What version of the CMS are you using?

We no longer support or develop the Player for Linux as the underlying libraries used are too volatile for us to manage so the last release of the Linux player only supports 1.6 series CMS (and then only in a limited capacity).

If you’re doing a new deployment then I’d strongly recommend 1.7 series CMS with a supported Player (Windows or Android)

Thank you for your answer, alex.

CMS version I’m using is 1.4.2 (I’ve read it going on “About” on my CMS; don’t know if I have done the right thing).

Just recently I’ve started to manage with Ubuntu and Xibo for a university project about digital signage and here they want me to use Ubuntu as server and Raspberry as client.
Since the beginning I’ve had a lot of problems with Ubuntu, because I was not used at it (I’ve always worked on Windows) and installing only the Xibo server took me an entire week on Ubuntu, instead of Windows on which I’ve installed server and client without any problem in one hour.

There are RPi images of the client floating about but the project has never officially supported it as they work really badly. Basically the hardware isn’t powerful enough for us.

You need to go back to your supervisor and explain that Ubuntu server is fine for the CMS (and that you should be installing version 1.7.5 if you want any help/support from the community) and that for the Player you need either a Windows PC (running the 1.7.5 Player) or an Android device (and an Android licence available from Spring Signage).

Thank you, alex.
You have been very kind to answer and explain to me in details.