Ok, I modified my game to reproduce those bugs. I found another platform bug, I call him "floor bug". If u look the video, when the player goes over the junction platform floor, depending on the position, it consider like the player is landing... but he's running without jumping.
I sended modified capx directly to support at scirra, because last version I was working on (r110.2) it works fine. From version r111 I begin to have those problems...
I modified the collision polygon of the grass to better show the issue. The arrows represent the keyboard commands.
Here's the videos (not in public list, of course!):
Hope you fix it like in previous version.