That's not the only glitch. It looks like it works fine but play around with it for a while and you'll notice some bizarre things. For instance, right now, my character unexpectedly disappeared off the screen because the physics objected landed on its head. I tried again to see what happens if the player is under the physics object and I got warped to the left or right of the screen.
Here, take a look at this .cap file. Put yourself underneath the falling object (let it fall on your head, in other words) and see what happens:
http://machriderx.googlepages.com/platform.cap
I don't think this is how it's supposed to be done. The two movements are obviously conflicting with one another. Call me crazy, but I thought there used to be option in the event sheet editor where you can include which objects can collide with the physics object. All I see now is an option to disable collisions with an object.
Maybe it was in an older version, but I don't want to go back and install every old version of Construct to see if it was there. If it wasn't then I don't know, I'm pretty sure I was able to get this to work in an older version without assigning two behaviors for one object. I thought this was a pretty basic thing that Construct could do without a problem (or any strange glitches, for that matter).