so, how flexible/reliable is this platform behavior anyway

I've never used it, I realized it'd be perfect to integrate with the movement system I'm trying to create now. I'm in rush mode with this project though, so if there's any nasty surprises that await, I'd rather know now rather than through experimentation.

how is the platform behavior as far as stability

and as far as being able to change it and add and change motion and such?

Stability is good, aside from the bugs that have cropped up recently. The one i had is fixed with the next build. There is some outstanding issues with air deceleration at the moment, not sure if that one is fixed in the next build though. Those niggles aside however, I push it in all sorts of directions and it is a trooper.

I've run into a number of bugs with it, but I've been told they have been fixed for .86 (aside from inconsistent ground speed in .85, and the air deceleration if it's above 100, after .62..I don't know whats up with those yet)

The only bug I've run into is jumping on slopes, but David said he fixed that for .86. Otherwise it's been working great for me.

Well I started playing with it and I can say it's very flexible (easily made a Megaman X clone almost perfectly), and if you keep away from complex customized stuff (like rotating the sprite on slopes and moving platforms where I've heard of upward-downward moving platform problems) it should be pretty much okay.