(I definitely have the reply I sent hours ago in my 'Sent Items', but maybe the Internet ate it. Anyway...)

Just to add to what MHL said, I notice your error concerns fileparam.py which is odd.
It should be present:
/path/to/volatility$ find -type f -name fileparam.py
./volatility/plugins/fileparam.py

Where did you get your copy of 2.4 from?

Might be worth grabbing it again from github.

Bridgey