These are used in my FS9 setup, although the plans, with a little tweaking, could be used in later sims. AIFPC will batch compile all 52 weeks of plans and also convert to FSX format on the fly if required. The AFDs are another matter! I think Greg Putz's sceneries are solely for FS9, so overlays will apply only to that sim in any case, since they are aligned to that FS9 scenery.
All AI helicopters land according to the same rules as Cessnas etc, they fly to the runway, do a rollout, and then taxy to a spot. What's different is the animations, which can disguise the fact that the helicopter thinks it is running along a runway. An animation lifts it into the air and it then appears to fly out and, after a few moments, lifts further into the air when the sim makes it rotate and lift off (the animation has already lifted it off). John Young's helicopters are animated to hover taxy, while the UTT ones don't do this. The UTT ones have cleverer animations as well, but these depend on their AFDs, which are very specialized.
What I've had to do is ignore the UTT approach, because it limited me to the UTT models, and there are many other AI helicopters out there, most of them on Military AI Works (AW139, AW109, Koala, EC145, Gazelle (Mark Beale made some great civilian repaints of those)).
The other limitation of the UTT approach is that a parking spot is tied to two invisible "runways" - every time! Each spot is its own mini-airport, and there are enough problems using overlays as it is without creating one for every landing spot. It wouldn't work at places such as Elstree or Redhill, near London, where there is a lot of helicopter activity. So these AFDs assume that there is a separate FATO (final approach/takeoff) from where the helicopters hover-taxy or simply ground taxy if they have wheels (like the AW139). It means one runway can serve as many helicopters as you can fit in. The "incident sites" near Winnipeg and Regina are mini-airports with 1 runway and 2 spots. With the flightplans being randomly generated there is always the chance of having at least 2 helicopters at any of of them. With the UTT system you have to be certain that only one helicopter will be there at any particular time.
It's very early days for me on the helicopter side of things.
What I can say is that a UTT helicopter into a UTT helipad will land on the spot and depart from it as well, and their helicopter packages come with a set of AFDs that you can program flights into and have them work like helicopters should.
Integrating helicopters into airports is another matter. Helicopters approach quite slowly (typically below 45 knots in the late stages of the approach), so it makes a lot of sense to have helicopters fly into an overlay if they're arriving at a busy airfield, since it allows us to separate their arrivals from the main traffic streams. Because they're slow on approach, it is also fairly easy to have them fly in from other directions using curved approaches, and then have them set down in an area away from the main runway. For example, at my FS9 Heathrow, they will arrive from the south, and before they reach the southern runway's centerline, will turn to land in an area between the cargo center and terminal 4 (actually marked for helicopter use).
I'm hoping at some point to get some time to experiment more with the UTT system, and see if I can replicate what they do, but with non-UTT models.
Edit: One thing I should also mention is that the plans need to be compiled with the cruise speeds as specified in the aircraft.txt files. The leg timings are created from those speeds in my planner, and I've set up the data for each aircraft from the "book" values, or between two "book" values if there is no mention of a normal cruise speed (some sources quote only an economical cruise speed and a max cruise speed, so I will tend to pick a speed 10-15 knots higher than economical and consider that to be typical).
