Set the keyboard input to space then create a and controller, then create a visibility actuator on the cube, uncheck the visibility box. then create a state actuator set the operation to “set” and click on the second box in the state actuator(the ones that look like the layers). now next to the controller buttons there is a little + sign in a circle click it and another set of boxes should appear. click on the second one(to change to the second state) and then create the same setup as the last time except this time leave the visibility box checked and click on the first box instead of the second box on the state actuator. that should work
This is how I would normally do something that includes multiple states, I really should start working with states properly. Someperson1, do you have any links to point me in the right direction for using states?