I did the first service today at almost 1300 kms. The charges would have been nil, but for my insistence to change the engine oil. The SA indicated that it's necessary only at 10000kms. Anyway, due to the engine oil and filter change the cost came to Rs. 1500.
SA mentioned that the sound during engaging the reverse has been reported by few others and has gone as a feedback to Toyota as well, but there is no clear solution so far. Anyway, I have my own workaround which I informed the SA. On autolock not happening after a certain speed, he indicated that this cannot be programmed with the remote locking unit that has come with the Etios.
After the engine oil change, the car feels a bit more smoother.