When the use check "Enable developper mode" in dialog 1:
<img src="http://www.programaths.be/construct/guimockdevmode1.png">
he is shown the dialog 2:
<img src="http://www.programaths.be/construct/guimockdevmode2.png">
The message is clear and does not give any clue about what the option does, instead it says only that you should enable that option if you know why ! It put the emphases on the bad aspects of it and not the good ones.
It's made to be sure that you don't enable it unless you really want to try it.
Each time Construct is launched, a nag screen is shown showing some options :
<img src="http://www.programaths.be/construct/usingdevmode.png">
It forces the "developper" to click on the third option.
Doing that, we can be sure that users who do not use this feature turn it off after a while. Unlesse they like nag screens !
The key in the registry can contains 3 values :
DISABLED (0)
DISABLED_ONCE (1)
ENABLED (2)