Let's start with a hint: Look at the episode title:
"Killing the Messenger"
Who could that be? And why "messenger"?
The messenger is of course our beloved bug. To make him a messenger, i.e. carry a crate, you have to first make sure that a bug survives.
Leave the crate and walk to the laser. Push it to the right, so that the next bug won't be killed. Yet.
When it passes you, it will pick up the crate. Move the laser back to its former position.
The bug dies, leaving the crate for you behind.
And that's it, folks!