"export XLIB_SKIP_ARGB_VISUALS=1" sets a shell variable before launching the program. A shell variable is a kind of environment setting. I'm not sure what this one is exactly, but I assume that when your program runs, it checks the variable in order to configure itself correctly.
The variable will only exist for as long as the process runs, and will be erased when the process terminates. There are ways to make shell variables permanent instead of using a launcher script like this, but since this one is only used by that one program, this way should suffice.
Edit: some google hits show that setting XLIB_SKIP_ARGB_VISUALS can help with a variety of programs, such as flashplayer, having trouble when compositing is enabled. Since it says "XLIB", it must be related to xorg.
Last edited by David the H.; 04-19-2009 at 08:29 AM.