QLab is a software application that is commonly used throughout the theatre industry as a means of cueing sound, video or lighting effects, as well as remotely controlling other computers or pieces of equipment.
Make sure you copy all files onto the hard drive of the computer rather than playing from a USB stick, for example. Files can be added to QLab by dragging them into QLab from the finder. Make sure sound files have output patch 1 selected then files can be played by selecting the file and pressing the space bar in Qlab. Qlab can do many more advanced things such as fades and groups. These commands can all be accessed by dragging them in from the toolbox on the left hand side and then dragging the target sound file into the action.