FRD doesnt run

I've a problem with FRD, it doesn't run .When I start it, the FRD image appears and then nothing happen...The java visual machine pops up which states " could not find the main class cn.vity.freerapid.core.main app: program will exit"

WAT DOES IT MEAN?

wat should i do to run FRD..

[wordrider.net]

-------------------------------------