The Phottix Cleon has gotten rave reviews from most people, but there seems to be a common problem with them. If your unit appears to work (will take an exposure remotely ok) but your camera won't display the image after the exposure, here is the problem:
The stem on the button in the receiver is too long, pressing on the switch, and keeping it in "half-shutter" mode all the time. All you have to do is remove the 2 phillips screws, pull the PCB out, and remove the plastic
button. Then, file the stem down some, and re-assemble the receiver.