You want to tick Portfolio->ChangePortfolioView->ShowClosedPositions.
ChangePortfolioView is about the 4th selection down on the left of the Portfolio. ShowClosedPositions is at the bottom of the list.
In the Portfolio, you may want to add in the Appreciation column.
That shows the appreciation or loss that would be recognized if
you sold that position.
There are also reports that may be of interest.
If you want to see taxable CG/loss is for your stock to plan what
to sell, especially if there is more than one lot to choose, take a look
at the Capital Gains Estimator. In Money Plus add the CapitalGains icon to the top of Money screen using Shortcuts...
CapitalGains->EstimateCapitalGainsTax
It's a little tricky.