The easiest way to do this is to start building UI roles in the Cognos namespace:

I would recommend setting up at least 2 different roles. One for admins with access to everything, and one for users.
Important note before we proceed: Unlike security permissions, the UI profiles are not additive. If a user is part of two roles, the one with the highest priority will determine which UI elements he can see and interact with.
Once you create the role, take a look at the properties.

Under Customization you're able to set all of the properties you want, including the quick launch:

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Paul Mendelson
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