Yeah that bit worked fine (otherwise i wouldnt have been able to open the console in the first placeDid you edit this file like the poster told you in the post you copied?
in renpy/common/00console.rpy
set "config.console = False" to "config.console = True"
works great for me. Only thing is it does not save. So I have to type c=15 each time I start the VN.
Are you launching the game, then putting the c=15 in before the agree screen?
Are you starting a new run or loading an old save file?
Cheers for trying to help anyway.