Guys need help!
today I switched on my quad and there was smoke!
checked the kk board and I could see the base metal expposed...tracks of the pcb gt damaged..
Dont know how it happened...

Seems the tracks are damaged, where did the smoke came from ?
Any crashes before ?

Check whether any components in KK board is burnt.

Checked others no issues...
no major crashes...

Is it possible to claim replacement? Will I get since its been less than a month frm date of purchase?

Replacement depends on your sellers discretion on returns and replacements, so you should check with him.
Altho I wont be surprised if seller denies replacement since its not easy to ascertain in such cases if its a user error or a defective product as you had used the FC successfully. Good Luck. 

Smoke only comes from the board if there is interchange of Electrical Terminals ... By chance, negative  is given to positive terminal and vice-versa

It was already flying...i just connected as usual to fly...
That too the location is where the buzzer is connected, which I dont use..

Please post close up images of your KK2 board.

Meanwhile Individually check other ESCs and motors for problems.

The lcd display switches on but no GUI

Top n bottom pics...

That is Ground track being ripped off, but this seems strange Even reverse polarity wont make it... How come the Copper track came off the board ? Due to heat ?

Did you used the battery voltage monitoring function ?

P.S: The board seems still, repairable

I hav low battery voltage alarm... Ill do wire modification if I domt gt replacement...

Guys am planning to get apm or cc3d... Its not possible to do wire modification for this...
so my question is is it possible to mount in this frame?
which is better out of apm n cc3d?

If you want more capabilities with your quad (RTH , Waypoints , Telemetry...) Go for APM. But if you need only stable flying, CC3D is better and is very very cheaper (16$ only) .
Both flight controller will fit on your frame

Ok 

I decided to get apm2.6 which is gud to get from?
this
http://rcmumbai.com/index.php/product/amp2-6-with-lea-6h-gps-external-compass/
Or this
http://robu.in/shop/apm2-6-ardupilot-mega-2-6-external-compass-apm-flight-controller-w-ublox-lea-6m-gps/
or this
http://m.banggood.com/APM-Flight-Controller-Set-APM-2_8-6MH-GPS-OSD-Radio-Telemetry-etc-p-960341.html

I want to get a quality one... No clones or bad ones..

Quote from: VTOLkarthik on February 06, 2015, 07:50:10 PM
....
I want to get a quality one... No clones or bad ones..

That is indeed a good decision. My clone APM came without two screws. Also, the barometer on my board is a lot more noisy than my friend's original APM board. Try and get the original APM 2.6 and not the 2.5.2 clone. It'll be worth the wait.

Oh, and the last link is for version 2.8 and not 2.6.

Any issue wit 2.8? Or advantages wen compared to 2.6?

I don't really know. I didn't get any official links upon a google search. It seems the 2.8 has a jumper for selecting between internal and external magnetometer, whereas, the 2.6 clones don't have an internal magnetometer at all. In any case, buy the APM with plastic cover. That way you can do perfect accelerometer calibration and add light protection for the onboard barometer.

Ok.. 
where shall I get frm?
which store is gud to buy?

Well, I got my clone from Satya (http://quadkopters.com/) and have no problems with it. Adding proper vibration protection and light protection did away with the baro noise too. My quad flies great!

You can get the original one from overseas. But, if you don't want to wait long and just want the quad for general flying, then go for a clone. There's differences in manufacturing quality only.

I wanted GPS as well...

Get a good GPS even if you buy an APM clone. APM's coolest features require a GPS and a low quality GPS will make them seem lame.

Check this one out:
http://www.quadkopters.com/product/flight-controllers/neo-7n-gps-w-3-axis-compass/

It's supposed to be better than the neo 6M (or 6H) version.

I have bad experiences with clones, tats the reason I dint want to...
I will look into it tho...

You may go for this APM complete kit if you are buying outside India
http://www.ebay.com/itm/131340217453?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

And all links you posted are clones - for original APM, you have to buy from 3DR.