Based on my experience 2.5 weeks ago, all check-in for the BA flight opened exactly 3 hours before departure, and not before.

Bit frustrating for a late-evening departure as we - along with many other travellers - were at the airport before that point.

Don't mix up rain with haze. At this time of year, KL suffers from a haze caused by forest fires in Indonesia, the haze/smog from which travels in the region. See this link for more: https://en.wikipedia.org/wiki/2015_Southeast_Asian_haze

Therefore although the pic posted looks like it's all rain, it will be a mix of rain and haze. When I was there recently the haze was very heavy, which on the face of it made it look like it was cloudy/damp/a big miserable. In fact it was achingly hot, and no rain.

After it rained in Singapore the haze was much better. It was warm and muggy but not really sunny- pretty much typical Singapore but the view was very clouded by haze most days. In Singapore you couldn't even see the boats out in the bay from the RC. Thursday as we left was sunny with little haze following a big storm.

Now in KL- it is much cooler than Singapore but much less haze. There was a torrential storm with lightening as we drove in from airport on Thursday. Yesterday was overcast with light rain pm and today is cloudy, but is is not hazy- you can see the hills in the distance.

Yes we were staying at the JW Marriott, so about 15 mins to the station, then 40 mins or so to the airport (train is 30 mins but waiting time etc).

T