You should also be able to find an error log somewhere within your home directory. I cannot recall if it typically goes above public_html or not. Looks to me that you probably have an fcgi build.
This is syntactically incorrect:
PHP Code:
$frm =
<form method="post">
<input name="domain" size="25"><br />
<input name="password" size="25"><br />
<input type="submit" value="Create Account">
</form>
echo $frm;
You can't assign a string without specifying it as a string. Simply put single quotes around that block and terminate it (the assignment is also optional):
PHP Code:
$frm = '
<form method="post">
<input name="domain" size="25"><br />
<input name="password" size="25"><br />
<input type="submit" value="Create Account">
</form>';
echo $frm;
The block with several if checks could be cleaned up by using ternary operations as well:
PHP Code:
$user_domain = isset($user_domain) ? $user_domain : getVar('domain');
$user_name = isset($user_name) ? $user_name : $mybb->user['username'];
// etc.
That is optional of course, it simply cleans it up into one line.
This probably won't work as desired:
$user_plan = '$whm_package';. Single quotes are non-parsed in PHP, so $user_plan would be the literal string '$whm_package'. Remove the single quotes around the argument value, and it will parse the $whm_package variable instead.
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