Equilibrium of systems in acccelerating frame

[serverxeon]

I've drawn the following FBD (using D'alembert prinicple)
[The N in my drawing is the F_A stated in the question]

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Assuming my FBD has nothing wrong, am I right to say that I am free to choose my torque equation about ANY POINT?

somehow my solutions vary depending on my point of consideration.

Torque eq about CM:
N + 2Fy cos(30) -2Fx sin(30) = 0

-or-
or eq about pivot:
N - 2mg cos(30) - 2ma sin(30) = ma

It just doesn't give the same solution.
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My other translational equilibrium eqs are:

ma - Nsin(30) + Fx = 0
Fy + Ncos(30) - mg = 0

 

[serverxeon]

solved.

my mistakes when pressing the calculator )=