Mate there must be something wrong youre doing. I checked those advices from users here and if you can do exactly as told, it shoud work. I only can think od you having wrong baseband for youre device, or incomplete download ...
Try older baseband or redownload it from sammobile.com.
Otherwise start looking around your town for someone with more skills who can take a look on that or someone having JTAG.
@Mohitash: wouldnt be worth it, to make some [HELP] or troubleshooting thread. So other threads are not spamed? Starting to be a bit disorganized around, we soon need general thread for our device, otherwise there would be complete mess

I suppose we have to find someone to pay on XDA stuff to make it for us finally.
Sent from my GT-S7562 using xda app-developers app