First, is not my EA, I just made some improvements.
It was started a year ago and several people contributed to this.
Current version is 15 but those that do not read or browse this thread use 9-1 because is newest version available on first post

Each EA have good parts and bad parts.
Mai problem of this one is big drawdown, not making profit.
v15 have reduced drawdown ~ 50% and increased profit ~10% compared with previous versions.

About ProfitMode and ProfitSkew, they are pretty much explained inside EA.
ProfitMode have 3 options:
2 = Will close all trades once ProfitTarget is reached.
3= Will close buys once ProfitTarget is reached by buy orders only, same goes for sells.
1= will combine 2 and 3 and will close orders on what situation came first.

ProfitSkew is active only with MoneyManagement=true.
MoneyManagement calculate ProfitTarget and ProfitSkew allow to adjust default ProfitTarget.
Example: if calculated ProfitTarget =2, using ProfitSkew =1.1 will result ProfitTarget =2.2, using ProfitSkew =0.8 will result ProfitTarget =1.6.

About optimization you can read this:
Backtesting/Optimization
or this
MQL4 Articles: strategy tester