well, you may try copying from between the code tags, and opening wordpad (start>>run wordpad) and paste to there. Then in wordpad, reselect, and copy and paste again (yes again) then paste to mirc remotes (alt+r) and it should retain its form..

As for wanting to know how, type /help halting default text. The ^ means "process before mirc does" meaning that you can do what you want with the text before mirc has a change to echo it to your screen.. For example, you have:
on 1:TEXT:Hello:#: { /echo -a $Nick said hello }

and now i say hello, you would see
Quote:

<kingtomato> hello
kingtomato said hello

Now, we use the ^ prefix:
on ^1:TEXT:Hello:#: { /echo -a $Nick said hello }

Now we see:
Quote:

kingtomato said hello
<kingtomato> hello


See the difference? Now, with a haltdef:
on ^1:TEXT:Hello:#: { /echo -a $Nick said hello | /haltdef }
Quote:

kingtomato said hello


Now, dpo that will all the events.. You echo your version before mirc does, stop mircs text from displaying with /haltdef, and viola! a personal theme >:S