To test commission assignment without doing a real payment you will need to manually add a payment.
To add a payment manually, go to ~wmtsystemurl~/admin/members in the members area and click on the billing history icon for the member you want to add commission for.
In the popup click the Add Payment link.
Enter a payment amount and date. For Type and Transaction ID you can enter anything or leave blank as it doesn't affect test results.
To apply the payment visit: ~wmtsystemurl~/admin/applyaffiliatepayments.php
An Member can mark someone that owes them a payment by going to the graphical lineage report.
On the graphical lineage report Members who have not paid will appear red.
Click on the red icon and then on the next page you will see a link on the right side where it says how much the Members owes you.
You can click on that link and then manually enter the payment amount you've received.
After you have completed this and marked an Member in your downline as paid they will still show as red as if they hadn't paid.
Also, in the view Members report they will still show as suspended.
The next time they attempt to login it will see that they are marked as paid and will change their status from suspended to active.