Equanimity is not the central point of practicing the Dhamma but a high end tool. The central task is discrimination of phenomenas, mindfulness (on the four frames of reference).
In doing so, there is seen where a possible disturbance actually comes from, arises, and by uprooting the disturbance (inwardly), recognicing that one can be not really touched but it is just the grasping, of what is not real, by oneself, there such equanimity with phenomenas arise.
What is an extreme disturbance really? The perception of a mouse, news on TV, a day without food, an executor, a tiger in front, a lost leg, a wounded belly, sreeming child, broken computer? What disturbes? The own missing coffee or missing food for the third world? Minimum 50 years more to suffer here, and not to speak after, again and again?
My person found "Equanimity is one of the central points of buddhism practice" merely disturbing, therfore:
AN 4.100: Potaliya Sutta: Potaliya {A ii 100} [Bodhi]. Here the Buddha points out to an wandering ascetic that alienation and equanimity are not the higherst virtues in regard of praise and blame.
and maybe: The Integrity of Emptiness
Because if having started practicing one will soon know for oneself, without building on disturbing thought constructions.
Enjoy solution, discriminatingly, direct perceived.
[Note: This is a gift of Dhamma, not meant for commercial purpose or other kinds of low wordily gains by means of trade and exchange]