Abhi17
If you can get NSENOW as your trading platform, that will be best. I don't understand how you tried with NOW if you do not have it.
Reliance Money Trading software is similar to NSENOW. Right click in the Market Watch, and see if there is a facility like "Snap to Excel", "Link to Excel" or "Load in Excel". If that is available, click on that and see if you get changing rates in excel. Call their helpline and ask them. If you get rates in excel, you are halfway thru. We can take it over from there.
Otherwise, download latest utility RTG3.xlsm. I have given the link earlier in this thread. You can disable NOW Realtime feed in that and use it to get Google realtime feed. Minus volume of course. Delay is hardly 3 seconds.