Notice: Undefined index: profile in /Applications/MAMP/htdocs/head/install.php on line 389
Ah the joy of procedural programming in a weakly typed language.
There are two issues here:
1. Drupal is reporting notices
2. Datastructure mismatches
The particular above notice is created when php tries to access a index of an array where the variable is not holding an array. In general this notice will not cause problems with Drupal functionality. You may want to turn off php reporting notices. To do this you can change php's error reporting.
In php.ini use:
error_reporting = E_ALL & ~E_NOTICE
In .htaccess user:
php_value error_reporting 2039