Hello Smitesh,
1. From question 3 you would have seen the value in order to change it. The default was 8.
2. I would think that if you want more than the default value of response, you would have to increase that default value to read them all and decrease the scan duration.
3. The scan duration is set at 4s. I'm not sure if the default of 8 is used to conform to a 32s total interval, so increasing it beyond that may be an issue. This is something that goes beyond my depth of understanding. You will have to research that one.
4. You can read either one by calling GAPROLE_ADVERT_DATA or GAPROLE_SCAN_RSP_DATA.
You should definitely download the Core Bluetooth v4.0 Specifications from Bluetooth.org. More precise detail can be found there. If you find out any more information or any of the above is incorrect, then please post it.
Thanks,