Having been provided with the wrong support e-mail address as detailed in my previous posting unsurprisingly I received no response from proDAD and the only option left open to me was to try to resolve the problems I was having myself. I started to trawl through endless webpages and Internet forums trying to find information which might help me get the standalone Mercalli system working and I finally stumbled across something.
I found a small software package called GSpot v2.70a which I downloaded. This small application is designed for examining video files with the idea of providing the user with information about the file and the video codecs which might be necessary to open the file. The application told me that the codec required was AVCL H.264 which means very little to me but did provide me with at least something to continue searching with. I initiated a search using this information and found an entry in something called the AnimeSuki Forum which suggested using something called the CCCP (Combined Community Codec Pack).
Armed with this information I continued my searching and ended up at the CCCP website where I downloaded the required file. I proceeded to install the codec pack and voilà I managed to open the file in the Mercalli package, I had taken a step forward.
As you might imagine this is not the end of this story by some considerable margin, I'll post the next step in the proDAD Mercalli V2 saga later.