I am moving there from uk in August with DCs aged 6 and 7 to join DH who started new job 8 weeks ago. Have just returned from 2weeks there with DCs visiting schools and some of the sights. So don't know about nurseries but a bit about ex pat neighborhoods from very recent property search. I will pm you when I have had few hours kip- very jetlagged and have just packed DCs off to school! When are you heading there? Would be keen to meet up once we both arrive. Main feeling was shock at just how hot and humid it really is but it will probably feel cooler to you!
My parents lived in KL for years (until 2009). They always favoured the diplomatic quarter as it is leafy and yet near to town. Loads of expats live there in low rise apartments (with pools etc) some local Chinese shops even stocked UK brands. There was an international/american school that most kids went to.