OSX installation instructions
From LuxRender Wiki
This page covers the setup procedure for LuxRender on Mac OS X systems. For the most part, this is a simple and straightfoward process that should be familiar for most Mac users.
Getting the installer
The current release of LuxRender is available here: http://www.luxrender.net/en_GB/standalone
You can scroll down to find the appropriate archive for your system. For LuxRender 0.8, two archives are avaible. One for 10.5 Leopard, the other for 10.6 Snow Leopard. You should select based on which version of the OS X you are running. The Snow Leopard build is also compatabile with 10.7 Lion, and is recommended for Lion users as well. The Leopard build lacks support for GPU acceleration and has fewer performance optimzations, and is only recommended for Macs actually running Leopard.
Both builds are universal for 32bit and 64bit Intel Macs. PowerPC Macs are not supported for LuxRender. These systems lack the performance (and in many cases, memory) needed for using LuxRender effectively. In addition, Intel Macs running 10.4 Tiger are not supported either.
To install the main LuxRender program, just open the .dmg and do the suggested drag-'n-drop install to "Applications". Thats it.
If you want use the terminal applications directly, you can use the script from "scripts_interactive" folder to simple start some prepared interactive action. For more sophisticated use, you may want to install the symbolic links ( just use the included scipt ) and have acces to all cmdline toll then from every workindirectory ( /usr/local/bin is alway in searchpath ).