octane 4.16 - environment question

[HHbomb]

Hi,
I don't really understand how the new environnement is working....
I plug a rgb map in Environment/Texture, and I can then check backplate/reflection and refraction.
ok it works.
But when I uncheck backplate for example, it is still there. same for the two other options ...
Anybody ?
Thanks

[Goldisart]

it would be nice if a new release to do small graphic and / or textual explanations of the innovations in the update