Re: Adding new pages... how?
Tiki is powerful and with that power comes a bit of a learning curve. It would be too long to explain how here but I'd suggest using Modules (in admin menu)for your About and Contact Us boxes -then they are always up in the left or right columns.
You'll need to set Permissions for editing pages. Look for a little key icon in various places around Tiki. You can set up groups, assign users to those groups and then give the groups permission levels. This way you do not need to assign permission on a per user basis. So set up a "trusted editor" group and assign only those people to it.
Note that Admin is kind of divided -if you click the Admin Home you'll get a bunch of icons for certain areas including Features and look and feel... Underneath the Admin Home choice in the left menu are other settings.
If you don't need image galleries and other such features you can turn them off in the Features section off the admin area. You might also poke around in the Wiki settings.