First clean up the variables window, in the code from Riamus2 there is no mention of %admin2 or %admincode2.
So, remove those 2 variables from the variables window.

Then the !add-admin command, at the moment I don't think its getting executed at all:
elseif ($1 == !add-admin) {
if ($nick == %superowner) {

So you have to create a new variable:
%superowner Duck_Power
Otherwise the entire !add-admin command will never get processed.

So eighter remove the "if ($nick == %superowner)" statement, or create that variable.