In order to test changes to non-publically-viewable sections of the Support Board, you need to grant the appropriate Privileges to the accounts you wish to use for testing.
The System account (system) is initially granted the priv admin:* when you run make_system.pl. This enables system to grant privileges to itself and any other account, via the Admin console using the command priv grant. All other privileges must be granted manually.
Logged-out Support requests are disabled by default to minimise spam. If you want to enable logged out Support requests, find the line in /etc/config.pl that reads
loggedout_support_requests => 1
and change the 1 to 0.
To change the validation reminder, which is added to support answers when the logged-in user didn't validate their email address, go to /admin/fileedit on your Dreamhack and create or edit a file called validationreminder with the desired content, which will likely include a link to the relevant FAQ on your Dreamhack. This requires the editing user to have the priv fileedit:validationreminder or fileedit:*.