In-laws taking away daughter in-law's jewellery and refusing to pay her mahr

Q: Is it right for an ex husband and his family to keep all the wifes jewelleries and refused to pay her maher? Last year his parents went for hajj but they still refused to give back what is hers. What's the Islamic understanding of this matter? She left it upto Allah but doesn't understand why they would steal her jewellery without her consent.

Looking at photos

Q:

1. I wanted to ask whether it is sinful to look at photographs? Or can we can look at photos of our mahrams?

2. We are not allowed to look at non mahrams. Does it mean that we cannot look at him even at a glance for once? For eg. We need to see for once, so as to know who is our brother in law, or neighbour, uncle i.e. just for recoginition purposes. 

Sitting on a chair and performing Salaah due to back pain

Q: I am having some trouble in reading Namaz and I want some suggestions from you. I am suffering from back pain together with sciatica and lumber disorder (pain affecting the back, hip, and leg, etc.). Owing to which I am unable to perform sajda and rukoo smoothly in the traditional way. Doctor says that it is caused by compression of a spinal nerve root in the lower back at L4 and L5 etc. by degeneration of an intervertebral disc.). So, Doctor suggested to me to avoid standing and sitting for a long time, bending/leaning of the back, squatting, lifting weight, etc. as it will lead in worsening my condition. So, in fear of Doctors advice I am using a stool/chair in offering salat. My question is, am I doing the right thing or is there any way in which I can read namaz? Please suggest ways in which I can offer my Namaz on a regular basis without having to compromise my health.