You can safely pump 92RON with peace of mind.
If your Latio encounters any problems as a result of pumping 92RON petrol, I buy you a brand new Latio to replace yours... COE included. 
BMW 7 series owner manual says min RON is 98.
But in the USA, highest RON available is 93RON, and I see the BMW 7 series there pumping 93RON petrol without any problems.
US and singapore use different Ron ratings. Their ratings at the service stations are usually in the PON scale. PON 87/89/91 are commonly available which is equivalent to our RON 90/92/95.
Minimum recommended Ron is based on the lowest grade that will not cause "knocking" in the engine. If you see manuals, they recommend higher grades for Middle east use because the climate is much hotter (hotter intake temps). So, the minimum recommended Ron is very much dependent on region the car is operated in as well.
Had a few friends from Arizona, U.S. They all say there must use higher grade or engine will knock.