Nikaah & Marriage Issues

Nikah conducted by a Barelwi Imam

Q: Our Nikah was conducted by a Barelwi Imam as my wife's family follow them. Is there anything to worry about, such as the validity of the nikkah due to it been conducted by a barelvi imam? I don't think I have to investigate what exactly people's beliefs or statuses are. Can I just assume the best and leave the matter?

Addicted to porn

Q: I am a married man with kids. However, I have been addicted to porn and cyber sex. My wife doesn't know, but i feel I cheat her and also commit a grave sin. I have tried to stop and repent many times but after a break of a month or so I start again. I feel hopeless and fear marriage break up and later on hell in my after life. Knowing I have made gunah-e-kabeera and that I have back tracked after repenting, is there hope for me? What should I do to cleanse myself and be hopeful of paradise?

Delaying in paying the Dowry

Q: If during the nikah, the wife gave the groom a specified amount of time to give the dowry. Example: The wife gave the groom till August 28th to give Dowry of $300. Since then the groom has put the money into a non-interest savings but the couple needed to take from the savings to make ends meet. The total amount put into savings exceeds the $300 dowry. Is the marriage still valid if $300 isn't given to the bride by august 28th?

Taking a second wife without informing the first

Q: Is it permissible for a husband to get into a second marriage without informing his first wife? Even after the second marriage he lied to his first wife and didn't let her know two or three years after the second marriage. Now the wife came to know and is in shock since the first marriage was 17 years old and the first wife was also quite young and a mother of four kids. She now wants her husband to divorce the second wife but husband is not willing. The second nikkah was also not announced in both sides.