The final versions of z26 added support for Mac OS X as the developer had implemented an OpenGL rendering engine, with this release however it did remove support for Linux.
For the older version z26 made use of the SDL Video library to render graphics. While z26 is one of the best ones at emulating the Atari 2600 it is however one of the more complex ones to setup. So prepare to have to do a bit of fiddling around with settings before you get started.
As z26 has now ceased in development, we recommend supporting and using the current only actively developed Atari 2600 emulator, Stella.