Pradeep,
I ran the update in ME 2014, currently Build id: 12.0.0-20131202, restarted ME and opened the workspace that was not letting me right click on the toolbar to customize and I still get nothing when right clicking the toolbar.
Window / Customize Perspective does open now from the menu, which it did not do before, but there is still a problem with the right click on the toolbar.
The workspace was created with ME 2014 and has only had a couple dummy 2014 test projects created, so there is nothing from previous versions in the workspace I am checking this against.
Let me know if there is something else you want me to try.
Thanks,
Ed