On a clean install of CentOS 7.2, I had problems with the libXp.so.6 shared library. I just wanted to point out that this was rectified by installing the libXp package. Google search results can be misleading. The following gets everything up and running:
yum install libXp
Half of my reasoning for posting this is that I'll probably be able to find this later. Hopefully it's helpful for others.