If you just want to add your prior cruises, go to "Profile" and under "Signature" list your cruises.
For instance, my signature says:
"A truly happy person is one who can enjoy the scenery on a detour."
Carnival Inspiration 2002
Carnival Elation 2004
Grand Princess 2004
NCL Sun 2005
Sun Princess 2006
[img]/countdown.php?month=10&year=2007&day=14&hour=17:00[/img] Caribbean Princess
And one Princess"open" booking!
***Edited to "Disable BBCode in this post" so the countdown clock format would show.