Every single step done by us is written by God. Then why, by doing good or bad deeds, do we go to heaven or hell, while we never perform any step without God’s permission?

Even that is written by God.

One can attribute the law of Karma for the grown up adults inflicted by deadly diseases like cancer, But how one can explain innocent children getting this deadly disease?

Everything in this world happens according to the Karma. Children get afflicted with deadly diseases like cancer because of their Karmas in their previous births.

Why does God create this world? Why does he make us suffer? Why can’t he forget all our sins and give us all Moksha instantly and wind up His Show? Is it His Lila to make us suffer?

When one participates in a motor race or wants to become a solider, he very well understands the risk involved in the job. Doesn’t he?
So, even after you witness so much of suffering in the world, you wish to continue the same lifestyle. That just implies that you are ready for the battle!
Joy or sorrow does not arise from any object or event as you imagine. It is in your mind. So, the key is to keep your mind aloof and unaffected from the happenings of the world. Yes. That is the solution. God is so compassionate that He has also shown the techniques, ways and means to achieve this state of aloofness. That shows His grace. What more? He shows no discrimination in showering His grace, based on caste, creed, religion, gender, wealth or power.

Why does Bhagavan Krishna give sufferings to even those who love him?

The hell is full of sorrows and the heaven is full of joy. But for anyone and everyone on earth, it is a mixture of both joy and sorrow.
To forget this mixed results of joy and sorrows, we should be totally immersed in Bhagavan Krishna’s eternal bliss.
It is only in order to get his most loved ones into that state, Krishna, an ocean of compassion, gives sufferings.

In age of Kali too there are people who are very much devoted to their guru and god, feeding the poor and the cattle, living lives in an orthodox manner. But I find these people suffer the most and the worst conditions in life. It can be due to their karma but when a normal man sees these good people suffer the most, he starts to believe that there is no use for dharma, god or guru for life. Why should God make such good people suffer without considering that these suffering would mislead the normal people seeing these devoted people suffer?

Let us assume that a person is packing up his luggage to go on a long travel and is scheduled to leave that day. After taking his regular meals, he realizes that there is a little more food left. He would then decide to eat up the remaining food also, because he would not be home the next day to consume the same.
In just the same way, those people for whom the current birth is the last would have to undergo their remaining Karma some way or the other. Hence good people wipe out their Karmas through such sufferings.

Why do God fearing people seem to suffer more than others?

A doctor administers anesthesia only to a patient who needs to undergo an operation. Likewise the Lord blesses with Bhakti, those people who need to work out their severe Karmas so that the effects of their severe karma do not affect them much.

Is karma applicable to animals too? Is there any difference on karma effects on man and women separately?

Karma is the same for men and women. As for animals, the animal birth occurs only to experience the effects of the karma carried over from the previous birth. During the lifetime of the animal, the karma is not accumulated.

What is Prarabdha Karma? How does it interfere in one’s life?

Everything in one’s life happens because of Prarabdha Karma and nothing else. So it is not a question of interference in one’s life, it is that which drives one’s life.

Do thoughts that do not translate into actions count towards karma? That is, does a bad thought count towards a negative karma? Also, do good thoughts and intentions that do not necessarily translate into actions count towards good karma?

In this Yuga, there are no punishments for bad thoughts. However, a continuous stream of bad thoughts will make a strong impression in you (vasana), which will harm you at a later point in time, if not immediately. How ever good thoughts will always result in good results.

Why is that nobody ask for sufferings?

That is because it is sufferings!