The project detects seeing inside only once. To reset the detector while remixing go to the stage and delete the (detector) variable. Don't go to the detector sprite in the editor before deleting the (detector) variable or the project will break.
The project exploits that the Scratch editor creates the variables that are used by a block when it shows the block. The detector sprite contains a hacked get variable block, that can detect when the variable is created. This is different from the other see inside detectors that I have seen because they usually check the mouse position or wait for the project to stop while the editor is loading.
