I recently posted a bug about platform behavior having issues with positive X movement (Platform / Positive X Movement Bug, received a quick fix from Ashley, thanks!). Seems that it wasn't limited to platforms. There's also an issue with slopes.
Basically, if you try to move the platform sprite to the right from a standstill when next to a slope that angles downward the platform sprite doesn't move until it has "accelerated" beyond a certain threshold. If you're already moving it seems to work fine, and it works fine when moving left or on an upward slope.
https://dl.dropbox.com/u/20459682/slope_bug.capx
This can cause problems while attempting to carefully navigate narrow sloped platforms in games. Hope you can solve it!