Sorry but I hadn´t seen your message!
No. I did not made any kind of drawing...
Just used my housing but never too deep, so it´s in an experimental fase.
I´m planning in modifiyng a new housing, so I will have to review this to make a new set of buttons (I will leave my 7D housing to my girlfriend who makes UW photography).
If you are still interested I can make the drawings then