You can choose what stats you use to rank your teams and how to rank your players.

In the Stats Model Editor (Menu > Manage > Statistics | Standings > Stats Model Editor

Click on Model for Players

The bottom left section fills up with the current columns displayed for the Singles Stats.

The bottom right section fills up with the columns used for Ranking the Singles Stats.

How the Ranking works

The top field is the one used unless there is a tie, then the second one is used and so on.

In this example, Score + is used to rank (highest score is first), if tied, the wins are used.  If also tied, the losses are used (lowest count is ranked higher) :

To change the Ranking

Click on the + in the bottom right section

Check all the columns you want to use to Rank the Singles Stats (and uncheck any that you don't need).  Click on OK when done.

You can also reorder the fields to change the priority by dragging them.