I'm not sure if you're using Mosaic or the Classic version. I don't know anything about Mosaic, but if you're using the Classic version you can add a tab and set that tab up the way you want it. I don't even look at the Portfolio tab really. Instead, I have each of my strategies listed as a tab and add the trades to the appropriate tab. All you have to do is click the '+' button at the end. Here's an example from one of my accounts:
(Of course, you may already know this and just want to know how to set up that tab. In that case, there may be an easier way, but I just right-clicked the headers and inserted/moved around columns to set up the page how I wanted it.)