I've already had a go at typing this - long detailed version, but I accidentally closed my browser and lost it all), so here's the shorter version.
What am I trying to do:
1. PLAYER sprite with bullet behaviour;
2. WALL sprite (top and bottom) of screen;
3. mouse click, PLAYER moves down and stops at WALL (flips angle)
4. mouse click, PLAYER moves up and stops at WALL (flips angle)
I've had a go, but my sprite seems to just go RIGHT, even though I've set the default angle to 90 degrees but it's not working.