Agree on the rigidity of the body. That's one of Preve's strong points. I would have thought an anti roll bar may be of help.

Do need to shove brake pedal hard when going downhill. I attribute that to the weight of the car and characteristics of the CVT (You might have missed an earlier discussion where we were talking about how after lifting leg off the accelerator pedal, the CVT doesn't slow down much).

When coming down Genting, I allowed the engine braking to do it's work & the car slowed pretty well. Didn't have to do much braking to get to the bottom of the hill.  On parts where the slope is steep, I used 'S'. When it's not that steep, 'S' feels jerky and I slotted it back to 'D' and the engine takes on a less edgy tone. The next time I come downhill on a daytime, I'll give the shifters a go.

Next part is just my personal opinion & by no means accurate. Difficult to put into words. So bear with me. Unlike a manual transmission, the CVT's engine braking is a pre-programmed thingy. It doesn't feel the same. You have little idea which 'gear' the CVT's on and have to judge/feel solely based on engine revolutions. Sometimes, I feel engine brakes the car too much and I wish to move a bit faster & apply some pressure onto the accelerator. Bear in mind that as the engine braking has kept revs above 2K rpm, you're instantly in turbo mode. As the car accelerates, programmed engine braking gets turned off. Even after I lift my leg off the accelerator, it takes short while before the engine starts braking again. So, don't go revving into a downhill corner too hard.

can connect to obd via bluetooth with iPhone?

FIXED

Proton recommends 10w-30, so its better to stick with it.
15w30, might be too thick...can affect the pickup.