1. Create a new goal <your_mod>Start
2. Add the following text in the KB section:
IF
GameEventSet("GAMEEVENT_GameStarted")
THEN
GoalCompleted;
Mmm, isnt an entry missing here?
THEN
InitStory();GoalCompleted;
Think its necessary for a safe story initialization, am I wrong?
No, it's not needed. If you use dependency on Shared in your mod (which is by default, unless you changed meta yourself) you already have __Start goal from Shared, which contains it, and it will be executed when it's needed.
Your ModStart goal purpose is, as above ALF said is to dock your mod goals in it and execute them in correct order (when game started, that's why there is a game started event)