houdini halo

has anyone here ever used houdini halo as a compositor for a blender based project. im trying to use its chroma-key feature, and i cant get it to work. also, there is hardly any documentation online. help will be greatly appreciated.

Try the official SideFX Houdini forum:
http://www.sidefx.com/forum/

You should get a better comp if you render in Blender with an alpha key.