IR trans uses the Ired2 software ( http://www.tinbert.com/iRed2/ ) for mac to translate the IR commands to something the mac can understand, and i think it is quite easy to use once getting to know it.
You start learning the BEO4 codes. For example V.MEM-Go and so on. Then you can chose if you want this code to do a keystroke or an apple script. I haven 't figured out yet if it is possible to make it do different commands in different programs with the same BEO4 code.
The Ired2 software has to keep running in the background for it to work.