There are some major changes in the program after v188.8.131.52b.
The most important is the new signal functions.
Let's see the "Indicator rises" logic for example:
Before it was calculated as: IF CurrentValue > PreviousValue -> Signal
Now the formula is: IF CurrentValue > PreviousValue + Sigma -> Signal
The new formula uses the Sigma parameter. This is the acceptable error when comparing double numbers. This formula improves the reliability of the backtest by removing the "noise" in calculations.
By default Sigma = Point * 0.5 for the indicators plotted on the main chart and Sigma = 0.000005 for the indicators plotted on a separated chart.
The computer cannot compare float point numbers unambiguously. For it 2.5 can be 2.4999998 and can be also 2.5000001
The Sigma function is shown in the source code page. The sigma mode can be adjusted from the config.xml file. If you want to receive results near to your previous ones, you can change the sigma modes to "0". This will make sigma = 0. (I don't recommend it to you)
Be sure that the results shown from the latest FSB version are more reliable.
(These are part of the forex backtesting secrets. Reading this forum you'll find many others also )