Login/Registration Integration with Joomla Templat

I am a (very!) new Joomla user and an even newer CB user. I am building a web site using Joomla (to replace a conventional existing site) and need to include a 'member area'. It is for a society and I need the members to log in with their membership number. Joomla Login does not allow usernames to be restricted in format, so I installed CB simply to get the login module which is brilliantly flexible in this respect. I Inserted the module into a login page which uses a custom template with the main site menu at the top. This works exactly as I want.
The problem is that when a new member clicks the link to the Registration page, the registration form appears on a page which seems to be based on my template (same background colour) but without a menu bar. This situation applies also to the post-registration acknowledgement and leaves the user with no navigation option other than BACK or entering a new URL - not very friendly.
I cannot see any way to force the registration process onto a page over which I have any control. The Joomla and CB templates seem to be independent. Can someone tell me where I am going wrong, or is this just how the CB registration process operates?

Problem Solved!
I created a new menu item to go direct to the registration form and assigned the menu to this. Now, when linking to registration from the login form, the menu appears as I require. Not sure why this should be the case, but since it does the job, I am not sure I care!