1. Ok the basically there one thing to understand first, when you turn, you turn from the point of view of you character (this the point you're moving when you change your FoV), wich means that to do a full 360, you will travel more distance if you have a low FoV rather than high FoV, so if you chose to convert your sens using 360 degree, your sens will be higher if you convert it to a game wich you play with a lower FoV (or slower if you convert to a game with a higher FoV). Wich means when you convert your sens you have 2 choices :
First, you chose that feeling of speed of your sens doesn't matter, you want the same 360 distance, then you chose 360 distance.
Second, you chose that your 360 distance doesn't matter, you want to feel the same speed when moving your cursor around, then you chose mdh.
If you convert to a game with the exact same FoV, both methods will result in the same converted sens.
So, when ADSing with a 1x with mdh 100%, you will move around the crosshair with the same speed as your converted game, no matter the zoom. Since zooming reduces your FoV, it will feel the same as your hipfire sens, but 360 will feel way faster (remember : lower FoV means more distance to travel a 360 distance, wich means higher sens to travel it with the same mouse distance)
2. You can choose between 360 and mdh in the top option in the calculator when you chose advanced mode.
3.mdh is calculated using straight lines because it easier to calculate this way, but keep in mind that what it calculates is the speed your cursor moves at.
So it works with any movement