I think i'd use subtle blues and/or greens against that brick, which i would use a sealer on to bring up the color a bit. White would be rather boring on the windows i feel, i'd use a darkish muted red or charcoal maybe for this detail. Such a pity to adopt boring western color codes when you have such a fabulous tradition for color in India. You don't have to go crazy on flashy color and can adapt it to a more modern feel. Very cute little house, i love it's details.

Looks like saltpetre which is leaching through the brick. You may hae waterproofed the outside but what about water leaching from the roof. Water will find a way.... Here is an interesting link... http://www.arcane-industries.co.uk/l1/p281-dampness-saltpetre-condensation.html

In civil engineering this condition is known as efflorescence this condition occurs due to capillary action of water in brick in which water contains diffrent salts comes on surface through voids of brick and evaporates and salt rest on surface as shown in image this salts may be harmful or not this depends on type and chemistry of salts generally it is not harmful

Greetings From Dream Design, As per your Requirements we are suggestion you some changes -White color -where It is Grey -Dark Cream -Where Blue as it will highlight that area and also well goes with Bricks -and Trims take Dark cream -For Shutters you can also use Cream color So use the White and dark cream with combination as brick part is already dark If you need more help Pls mail us. Thanks Dream Design