We need 1 tiledbackground and a solid behavior on it we design the wall layout like bellow and drop a sprite call it player and attach the behavior platform on it.
We also need to add the keyboard plugin, for this example we will use the default keys on the platformer and up arrow key shortcut
On the Event sheet we have
And we should have something like the bellow image
If we run the preview we will slide slowly if we near the left or right wall, and while we are sliding down and we press up if we on the left wall sliding down then we are pushed up and towards right side and same for right side but we are pushed towards left.
If you didn't managed to recreate the example by reading the text above then don't worry there is always a file at the bottom of the page usually after this part of text.
"GIMEEE!!" - Download