If this task isn't supported by a script, then, of course, it won't work.
OBJECTIVE_ACTIVE -- activate the task;
OBJECTIVE_COMPLETED -- complete the task successfully;
OBJECTIVE_FAILED -- complete the task negatively.But now, another question arises: how do I support it with a script????
It's not just about writing OBJECTIVE_ACTIVE, right???
P.S.: I would advise you to start with the design of the future map. Then, when you come up with a plot, you can start working on the scripts. You won't be able to figure out everything you need in advance.