The biggest problem you have is the cranking enrichments as currently in 1.1.44 you dont have any, just prime pulse.
Dave said he is using different injectors, however you should still be able to work out the amount of fuel required to start these engines if you have the pulse width Dave uses and the flow rate for each injector.
Everything else is trivial, but you NEED to review EVERY setting between the two firmwares, and adjust where required. The two firmwares are a world appart so you have to expect that not everything will be the same.
1.1.47 has nitrous retard, and should be pretty much a stright swap from 1.1.44 with a few extra features you will have to configure. Its what I am running. I think this was the last of the megatune supported firmware before they started changing table sizes and such, but there have been reports of bugs in acceleration enrichments. I did notice a delay on acceleration enrichments, but there is a number of different features that are configurable that were perhaps causing this. I never got enough time before I melted a piston on 25hp jets would you believe!!! something wrong there!!