A few questions about scripts.

1. If the txt file is located in the main map folder (i.e., Maps/SingleMissions/map_name), you can specify the path to it as follows:

GetMapDataPath()..'filename.txt'

2. The simplest way would be to attach the OBJECT_CAPTURE_TRIGGER to all necessary objects and create a variable to store the number of captured objects:

huts = {table_of_script_names_of_objects}
huts_captured = 0 -- number of captured objects

for i, hut in huts do
  Trigger(OBJECT_CAPTURE_TRIGGER, hut, 'CaptureHut')
end

-- function that is triggered when an object is captured
function CaptureHut(p_owner, n_owner)
  -- is the new owner of the object a player?
  if n_owner == PLAYER_1 then
    -- increase the number of captured objects
    huts_captured = huts_captured + 1
    -- if all are captured and the objective is active
    if huts_captured = length(huts) and GetObjectiveState('objective_name') == OBJECTIVE_ACTIVE then
      -- complete the objective
      SetObjectiveState('objective_name', OBJECTIVE_COMPLETED)
    end
  else -- if the new owner is not a player?
    if p_owner == PLAYER_1 then
      -- decrease the number of captured objects if the player was the previous owner
      huts_captured = huts_captured - 1
    end
  end
end

3. MoveHeroRealTime() will be helpful.
4. OpenCircleFog() will be helpful.

P.S. I advise you to read the manuals more carefully; the questions are very basic and are covered in any guide