All these ones don't actually do something when space-bar is pressed but do show the animation.
The same thing happens with Gui buttons. They do show the press animation, but they do not actually get pressed and do not send an on_gui_click event call.
Now to checkboxes, they get the animation, but also loose their mark in the middle (only visually). Like the buttons, no event call is done.
To reproduce:
- Press a gui item
- press space
- Look closely to the spot you just clicked.
EDIT: just checked, it still happens in .35