Re: moving a 5 frame nuc into a Warre
That board is about as good of an adapter that you could get. The bees will actually work up, faster, but as odfrank said, going up into an empty box will be an issue. If you try to make them go down, into the Warré box below, that's going to be a long drawn out process also.
What's happening to the frames from the nuc? If you won't be using them again, cut them down so they can fit into the Warré box and just transfer the whole thing straight into the Warré. It would mean discarding the end bits of comb, but they'll just have to be sacrificed.
As you add new Warré boxes under your first one as your hive gets bigger, you will eventually end up with the top box full of honey and you will remove it. At that time you can get rid of the old langstroth combs you put in it to transfer in the nuc.
44 years, been commercial, outfits up to 4000 hives, now 120 hives and 200 nucs as a hobby, selling bees. T (mostly).