Spouse visa - bad immigration history

[jimmyjames]

I am a British Citizen (otherwise than by descent) resident in the UK, and am trying to get a Spouse Visa for my wife and register my child as a British Citizen.
My wife is Thai and resident in Thailand with our child who was born this year - before our wedding.

On the Birth Registration:
you are asked to provide evidence any previous marriages are dissolved.
-neither of us have been married before, do we need to show evidence for this? (if so, in what form)
As the child is illegitimate I have to attend an interview and submit a Domicile questionaire.
Do I need to support this with a file similar to a Visa application - P60, employment reference, proof of UK residence, evidence of relationship etc.
Is it worth getting a DNA test in Thailand to prove paternity?

On the Spouse Visa:
My wife travelled to England on a false passport. We met and she lived with me for 1 1/2 years and did not work, (I have no official evidence of cohabitation only photos).
When she returned to Thailand on her own passport she was stopped, questioned, her passport was marked "seen at LHR no visa". In Thailand she paid someone to avoid passport control.
Also in the past she overstayed a Tourist Visa in Singapore and her passport was stamped by the Singapore Passport control.
My worries are obviously about her immigration history - is there any chance of a Spouse visa in her situation?
If we can successfully register my child as British will this be a mitigating factor?
If we don't submit her old passports and don't mention her time in England is there a chance her application could succeed as the Thai Authorities have no record of her Visa transgressions?

[Tom123]

from the stories I've heard I would by all means not tell the officials about this if you don't have to!!
Whatever you do, I think your gonna need professional legal help.

[London coool]

So far as your wife was apprehended by an IO on embarkations control at Heathrow airport and her passport was endorsed "seen at LHR no visa", then a report has gone to the BHC Bangkok. It would be picked up by the ECO...as far as it contains the same bio-details.

If your name and your wife's name appears on your son's birth certificate you do not need to provide a DNA test result ,except you are asked to do so.