How can a puja room in the South-East be corrected?
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.
Related questions
Can a photo of God be put up in the Brahmasthan?
Yes, there is no problem in putting God's photo in the Brahmasthan, because it is the place of Brahma.
Do paintings or decorative idols of God also need correct placement?
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.
In my East-facing house the temple had to be on the North wall, so the gods face South; is that wrong?
Do not make the gods face South; it brings heaviness, for example interviews go well but give no result. Place them on the West wall instead so that they face East.
Is it right to build a temple in the kitchen?
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.
Our mandir is in the Brahmasthan and Lord Shiva faces West; is that a problem?
Do not worry about Lord Shankar facing West; worry only about the South, and even Hanuman ji may face South. If a deity ever faces a wrong direction, fix a mirror directly in front of the deity.
The West is best for the temple. If the West is a balcony, can it be covered and the deities hung, since they are not consecrated?
Hanging is ruled out for consecrated deities: if the idols are pran-pratishthit (consecrated), they must never hang.