OK so I attempted the pour last night. Had a crack at sculpting a Nemo....hmm my sculpting skills need working on is all I have to say about that. Maybe next time. The resin was easy enough to mix and has a very long (24hour) curing time which it seems is both good and bad.
Good because I don't need to worry about rushing and getting air bubbles in the mix and pouring it all in 60 seconds.
Bad because as it turns out the 1st attempt at this I interpreted the "the resin will cure faster if left next to a gentle heat source" part of the instructions as "hey if I shine my hobby lamp with daylight bulb, that will do the trick!!". These bulbs generate a fair more bit of heat than I anticipated and consequently it softened the Plasticine I was using to keep the mold in place to the point where when I checked it 30 minutes after the pour, the mould was no longer flush and I was leaking resin. Queue the A-Team music and a rather panicky clear up, reset of the mould and repour. Consequently I have no idea how the second pour is going to turn out but I suspect it will not be the neatest of finishes. I will remove it later and post up a pic.