Go ahead and add them to the same items. Just leave alone any new ones, I'll assign them numbers later (unless you want to do it yourself).
But what's the point of listOrders for research? I mean, for items and ufopaedia it's obviously to make them appear in the desired place in the buy-sell menu / ufopaedia menu, but for research.. yeah there's the list when you select a new project but I frankly never noticed there was some kind of order in there lol.
However I'll add theml in the next version (I have to understand how listOrder works first, though), and I'll add Italian text too.
What do you mean by special missions?
I tried to have MiB do a terror-like mission, with a ufo (using the graphics of a house, so there wouldn't be any actual ufo on the battlescape) spawned grounded (green icon) for 10 hours, and forcing a URBAN terrain (with civilians too) for the battlescape.
I also tried to have MiB build bases, again with a ufo (using the graphics of a large warehouse) spawned grounded for 20 years, with a 2nd stage following the first battlescape battle, using the X-COM base terrain.
I couldn't get them to work for more than one reason, so I scrapped them (for now).