Custom Login form question
Drupal does not support different login forms. User is either logged in or not, and his privileges depend solely on his roles.


You can put a block multiple times on one page using MultiBlock
User has his roles, check them normally. He will have his role no matter what form will he use.
If you want dynamically give roles, yes, you need to write your own module that will act kinda like login handler, but be prepared to live with huge access permissions problems.