UK marriage certificate - tier1 general dependent visa query

Hi guys,
Urgent clarification required...

My visa status : tier1 general visa valid till 2016
Me and my girl friend are in relation since 2 years.

she came to UK in December 2013 with visiting visa to celebrate X-mas and new year eve with me(3weeks visit).we decided to get marry in UK, So she fly back to UK and we booked our marriage day in London register office. so we are going to get marry in 2weeks in register office and on same day we are going to receive our marriage certificate and next day we are flying back to India to see our parents(flight tickets also booked)
Now my doubts are
1) if we marry in UK and submit UK marriage certificate with photos and apply my wife tier 1 dependent visa in India , they (UK embassy in India) will accept our marriage certificate? Is Our approach valid?
2)if answer is yes for above question , normally every register office in UK provide proper marriage certificate on same day ,so are we need to go legalisation office in Milton Keynes for getting stamp on marriage certificate ? Or certificate given by register office is sufficient to apply tier 1 general dependent visa?
3) any one kindly explain me how to stamp our marriage certificate with in 2working days (marriage day and next working day) because after marriage next day we both flying back to India. So we have hardly 2days in our hand.
4) my girl friend already had a visiting visa and valid till may 2014 whether she can able to apply dependent visa in India in April 2014?


We already have our communication emails, money gram vouchers, flight tickets etc to prove our relationship is genuine.
We both maintaing above 800 pounds in our accounts

We are thinking like once we reached in India I can take TB certificate and apply dependent visa for her. So once she get visa we both come back together.

Can someone kindly look into these doubts as I mentioned above and please reply me back?
Thanks
Prab