Mirror Custom bone shapes problem.

Hello. Im having an issue when trying to the mirror the bones on the left side of my character to the right side. In edit mode the bones look like they mirror correctly but when i got to pose mode i see all the custom shapes that i have used for the bones have rotated. This is my first model so its probably a noob problem, but its still very frustrating.

Also i was wondering if the bones and the attached meshes need to be symmetrical for the pose flip (ctrl+shift+v command) to work in animation because i carried on with my model by manually rotating the custom shapes into place then when i tried to flip the pose in animation it didnt work correctly.

I did use the custom_shape_orientation plugin, maybe that could be the issue