You may have to manually delete these left over remnants in order to have them completely removed from the page.
As for why it is not working for you it is difficult to say. I think it may be best for you to create an entirely new page and try this from scratch to see what result you get. I think it will be a little easier this way.
On this page you would want to start with the recordset on the page, then craft the display by dragging and dropping the bindings from the recordset onto the page. Once the bindings are on the page you can add in a form around them and add in a check box.
Once you have added the checkbox you would then highlight the bindings and checkbox and apply the repeat selection server behavior. After you have successfully applied that you should be able to add in the multiple delete without issue. Please give this a try and let us know and what point you are having issues if any problems arise.
