I know where to go then. Just in case the developer will approve the proposed changes re: use of common area and modification of external structure of the building. My understanding is, under the regulation, common area cannot be used exclusively by any unit owner; moreso to modify the external structure of his/her unit to invade a common space (e.g. installation of grills).
Best to consult a lawyer also before you bring your case forward so you have the legal aspect covered.
As for modifying common areas, baka may tax implications din yan to the association so explore that angle as well since all members pay the taxes for common areas.