Touching the Skin
Question :

Once I have completed wudhu, is it still valid after I touch my husband or when he touches me after he has completed wudhu?

Answer :

Touching the skin of the opposite sex does not invalidate the wudhu.

Pre-ejaculatory Fluid
Question :

If pre-ejaculatory fluid (or Cowpers fluid) is passed after ablution, is the ablution valid?

Answer :

Discharge of the said liquid does not invalidate the ablution.

Temptaion Towards a woman
Question :

If after ablution a person is tempted towards women, does this invalidate the ablution?

Answer :

The ablution is not invalidated by such a thing.

Bleeding Gums
Question :

Do bleeding gums make wudhu void?

Answer :

No, the bleeding of the gums does not invalidate the wudhu.

Woman Seen by Non-Mahram
Question :

If a woman after wudhu is seen by a non-mahram person, does her wudhu become invalid?

Answer :

No, this does not invalidate the wudhu.

Gas Movements
Question :

Sometimes during prayer I feel internal movements or gas, such that it causes doubt about whether I have passed gas or not. Should I act on the doubt and consider my wudhu void, or do I ignore it until I am certain that gas has actually exited?

Answer :

You should ignore such doubts. You can continue your prayer.

Istibra
Question :

A person after urinating performs wudhu. He then performs prayer. During his prayer he feels that he has excreted a fluid from his urinary organ, but there is uncertainty as to the actual type of fluid. What is the state of his prayer now? Is it invalid?

Answer :

If he did istibra, which is the process of ensuring that there is no urine left in the urethra, or if he knew that the urethra had no urine left because he waited for some time after urination or because of any other reason, then the prayer is valid and he should not pay attention to this doubt.
If this was not the case, and he doubts whether the liquid was urine or not, then he should treat it as urine, consider the wudhu and the prayer as void, and purify the body and clothes that the liquid came into contact with.