I build the mech after your LDD instructions, but the back always falls. You should try to modify the brick that holds the shoulder pads.
I made my own mech and i made a LDD project. The color scheme is exactly like the real one that i made (i didn't have golden pieces)
Hope you like it!
P.S. I will put pictures of my version if you like it!
samurai_x_power_suit_v3.lxf