Construct 2 r 163 (32 bit)
I've faced the problem when I was working with skeleton animation using Spriter plugin. The bug is a problem for "complex" games.
But it is easily reproducible with basic Construct 2 plugins.
Here is how:
1. Open bugreport.capx
2. Run it.
3. 1-3 platform sprite objects should fall through the first thin solid floor.
4. If you don't observe the problem then increase "Rate" property of "Particles" object located on Layout until reproduced.
5. Bug is not observable if you set "Particles" "Rate" to ~0.