Hi Robert,
If you can't login try using the password reset feature to gain access, or send in a 2nd level support request and we can take a look.
Regarding how to edit the main page, because CMS Builder let's developers create a custom CMS, there's not set format of what they can build, and they may or may not have included the front page in the CMS. Best to have a look through the menus and see if there's anything, or review the main page code and see if there's any PHP code in there.
Hope that helps!
Dave Edis - Senior Developer
interactivetools.com