Use a separate shopping cart for your wish list. Then store the results in a database record.
To pull it off you first need to keep track of the customer, so you will need to use SecurityAssist to provide login and only allow users that have logged in to add to the wish list.
Then use "Store Cart Summary" and "Store Cart Details" to store the wish list cart in separate tables including a userID from the logged in user.
Then you can repopulate the wish list cart when they log in using the "add to cart from recordset" functionality by filtering to view the logged in user's recordset.