Shift surface problem

Hi Everyone,

My name is Marc, I'm a french technician (English is not my native langage sorry if I make mistake)

I need your help, because I would like to create a lower offset 10.2 mm from my upper "skin".

I created the shift of the surface without difficulty, but I can not properly shift the "holes".

I get discontinuities and overlaps.

Please find enclosed my ".asm"

PS : I havent create the brace/spacer.

Thank for your help.

Marc