The validity of any act done or proceedings taken under this Act shall not be questioned on the ground of—
(a) the existence of any vacancy in the membership of, or of any defect in the constitution of the Corporation;
(b) the contravention by a member of the Corporation of the provisions of section 6(5); or
(c) any omission, defect or irregularity not affecting the merits of any act done by the Corporation.