Alley should be able to play what your OS's native player can. On windows this would be Movies and TV, and on OSX it's quickview.
If you have issues with files that the os can play, you can send them to us to
mail@resolume.com so we can take a look.
Software developer, Sound Engineer,
Control Your show with ”Enter” - multiple Resolume servers at once - SMPTE/MTC column launch
try for free:
http://programs.palffyzoltan.hu