If you intend to build plug-ins for Mudbox using the SDK, you need to install and configure Qt.
Plug-ins built using the Mudbox SDK require the GCC 4.1.2 compiler.
You need to define QTDIR in your .bashrc/.cshrc/.tschrc file as appropriate. QTDIR should be set to the QT include directory on the machine. If QT is installed in the "standard" location, that directory is QTDIR=/usr/local/Trolltech/Qt-4.8.5/include.
If you get an error about plug-ins failing to load when you launch Mudbox, either disable the SELinux enforcing functions, or set to 'permissive'. You can set these options using the SELinux Administration panel under System > Administration > SELinux Management.