Creating Custom Drupal 7 Registration Form
I have tested the code and it's almost working as it's intended to be. One thing to note is when you placed the template file inside of the templates folder then the following should work.

On the icompany_theme() function, change the path value from 'path' =&gt; drupal_get_path('theme','icompany'), to 'path' =&gt; drupal_get_path('theme','icompany') . '/templates', which specifies to look for the file inside the templates folder.

Then flush your caches.