DilanDog,
I opened a new project in AC 6.5, went to the object tool,
found the object "curtain wall glass par", placed an instance
of it in the plan, and then rotated it in the Z axis by the
method of turning it in the objects settings dialogue box
with the curved arrow in the plan preview area.
This worked as expected, the object rotated in the Z axis
in plan and in the 3D window.
I must be missing something.
Thank you,
Peter Devlin