Also known asmandirtemple at homepooja room
In a building whose East-West axis is longer, place the deity (prabhu) in the exact West so that it faces East. When the deity looks to the East, the direction corrects itself.
It can be balanced with methods taught later. A good immediate remedy is to place the deity in the exact West of the home so that it faces East; when the deity looks to the East, the direction corrects itself.
It indicates negative energy at that place. Dowsers and highly sensitive persons feel such energy much more strongly, and your body was able to sense it; talking about it connects you to it again. The teacher has had similar reactions at sites, once with his whole body going limp, red and sweating and with severe loose motions.
Yes, whether the mirror is in the house, the temple or anywhere else.
When Adi Prabhu (Shiva) did sadhana on Kailash, the friction produced heat that began to melt the mountain, so water matters most for cooling this place; Shikhi's energy stored with water also spreads through the house and keeps removing about 50% of its vastu doshas. In the drawing room the family sits as if in sadhana and makes its plans and policies, and in a conference room others are convinced with one's ideas and vision and given targets. Worship of Adi Prabhu (Shiva) in a puja room here raises the energy further; an office and a borewell also suit this pad.
Elephant figures should stand on something solid, not hang in the air. The temple can stay, but a temple with elephants is better placed in the West.
A small temple at home should not have a big dome or shikhar; keep it small.
Hanging is ruled out for consecrated deities: if the idols are pran-pratishthit (consecrated), they must never hang.
Energy keeps entering through the main door every moment, and at night spirits, devas and angels also move about and enter the house; if they find feet pointing at them they take it as disrespect, as if being kicked, and the sleeper suffers ill effects. The rule dates from when large families made some children sleep in the main door hall. For the same reason never point the feet towards the temple or God, a cow, religious books or the tijori where Lakshmi resides.
No, building a temple in the kitchen is not right at all. Keep only a small kalash in the Agni kon (South-East) and a small photo of your guru there; that is not a temple. Guru (Jupiter) and Mars are friends, so the guru's grace supports the kitchen.
If it holds a consecrated (pratishthit) idol, the idol should be moved. If the idol is not consecrated, there is no need to worry, as these rules apply to consecrated idols.
Yes, there is no problem in putting God's photo in the Brahmasthan, because it is the place of Brahma.
Yes, they also represent a planet and should be placed correctly. A consecrated God's photo should face North or East, or West if that is not possible, but never South; South-facing is for the photos of ancestors who have left this world.