In order to calculate the max unrealized gains on your account, you need only the following values - 
 
1. Account Value
2. Max Trailing Drawdown (under equity button)
3. Evaluations drawdown value (please see products page)
 
 
 
 
 
 
Account Value (157,699.88) - Max Trailing Drawdown (4,684.35) = Liquidation Threshold (153,015.53)
 
then
 
Liquidation Threshold (153,015.53) + Evals Trailing Draw down value (5000) = Max Unrealized Value (158,015.53)