Platform Riding - Unwanted vertical trembling/shaking

Hey, Guys!
I'm implementing a Platform Riding behaviour, right now, and I have the problem that the Player always seems to jitter/shake by 1 Pixel when he's standing on the platform that's moving upwards (especially when it moves downwards). I noticed it in other Stencyl games, too, like this one (http://www.stencyl.com/game/play/10859).
Is this a known bug with the physics engine, maybe? Is the collision detection "too slow"?
I'd really love to know. Thanks in advance! :-)

Okay, no solution for the vertical movement, yet, but I think I know the root of the problem that also leads to my Player not sticking to the moving platform.
My Platform Moving behaviour uses the "Slide to/by" block which doesn't seem to use a speed value but rather moves the actor manually step by step, I suppose. I debugged and it looks like the platform's speed is 0.
Hmm, I guess I have to rewrite the platform motion code :/

I had a similar problem.

Are you changing the position of the rider based on the position of the platform?  Are they both non-sensor actors?

If so, I think the jittering is caused by the collision system.  Every time the player's position changes, it slightly overlaps the platform.  This causes a tiny collision reaction.

I'm not sure how practical it would be for your game, but my solution was making a specific animation for riding.  This animation was set to a sensor, which stopped the collisions thus stopping the jittering.

Hmm, that sounds plausible. Not based on the position but I'm giving the player the same speed as the platform while standing still. I will keep your method in mind. I'll try figuring out how to make my approach work first, though.
I'm using "Set speed to" now, instead of "Slide to/by" for the platform and now the player stays on it when moving horizontal, but only in some weird circumstances. Like only after I walked a bit or saved or whatever. Totally arbitrarily, aaargh I'm so happy when this will finally work as it's supposed to!

I tried speed and position, and they both get the jitters.  Mine was inconsistent too.  It drove me crazy for awhile too.

If you can find a solution that doesn't involve making either the player or the platform a sensor, let me know.  If you want to try making the platform a sensor, I'll can help.