1) Usually, it's not necessary.
2) Write the monster's name as you want it. The monster type is its identifier, a number, or a variable; you can find these in the HOMM5_A2_IDs_for_Scripts.pdf manual file. Quantity is the number of monsters in the unit. x, y are the coordinates. Floor - 1 for dungeon, 0 for surface. Mood - the chance of the monster joining. Courage - whether the monster will join/flee/fight; MONSTER_COURAGE_ALWAYS_FIGHT is suitable here; mood does not affect this. The monster's rotation angle in degrees, 0 means facing south. Growth - whether the number of monsters will increase over time (1 - no, 0 - yes).
2) Oops, I guess I didn't phrase the question correctly. I meant a DEMON HERO, not the monster itself. Although... this script will be useful to me as well.

Прокрастинирую...
"...Завтра станет лучше
но солнце так и не взошло..."