You may be able to accomplish what you need using field-level security. Go into Manage Security Roles and click the Advanced button. You can select what fields a security role has access to. Combined with Field Templates it may give you what you need (fields that a user does not have access to will be disabled).
As for the missing fields, you are referring to being able to remove/disable the tabs, right? This is on our list and if it won't be in at release it will be added in shortly after. The Customer Portal tab in particular is controlled by two fields available in Field Templates called Customer Name and Publicly Viewable. If neither field is selected, the tab is not visible.
Dragan Marceta
www.Axosoft.com