Hi
I think there will be a new variable for what if p/l in the next update.
At the moment you can use a formula:
http://community.welldonesoft.com/troubleshooting-8/what-if/Using the back first formula in the above link, your trigger should look something like this:
green up based on profit% 0.01%
Condition:
selections trigger expression (back_payout-lay_payout)/lay_price-back_matched is greater than 5.00
the above should green up a back bet only if the "what if" p/l is greater than 5.00
untested - please play with it in test mode or Time Machine