Lpg will need set up once fitted to your car. It should run the same as you have the same engine, I guess, but it's wise to set it up and check all is well. Not lean, etc. Pluss there's no guarantees it was running correctly on gas before.
So does it come with a diags lead to connect the Ecu to a lap top? You'll need this to set it up correctly. Brc are a bit tight with "non trade" people fiddling with "their" ecu's so set up might be tricky, as leads are hard to come by for these, last I heard. In fact, before starting, it might be wise to see if you can get the brc software downloaded to your lap top first. It might not be publicly available.
Although ypu could take it to a brc specialist, and pay them to do it, but there is a cost to that.
Otherwise, should be fine. There's a couple of bfc ssystems on members cars here. They work ok afaik.
Does the car in the pic loose coolant, btw? There's coolant residue on that vapourisor and associated pipe work in the pic. See that brown/pink stuff? Might have a leak. Or it had a leak in the past, perhaps...?
If you rebuild it on the other car, try not to use jubilees, they often leak. Gm spring clips, although a pita, are much better at holding even pressure around rubber pipes. You'll get less leak issues with those, especially in the early days after fitting when stuff settles down.