Registax 4 problem.

Hi Folks
I have just bought a DMK21AF04 firewire camera and have shot an AVI
sequence of Saturn but can`t seem to get Registax 4 to open it and just
get a `failed to start AVI decompression` message.
Does this mean that my camera is compressing the AVI files and Registax
can`t open it or is there something else I`m missing ?. I `ve not used
v4 before and its the first time I`ve used this camera so on a bit of a
learning curve at present.
Cheers
Steve