strange errors in back-tester

 

the back-tester reports incorrect equity and my EA starts acting wired.

What might be the problem?

Alert("AccountInfoDouble(ACCOUNT_BALANCE)= ", (AccountInfoDouble(ACCOUNT_BALANCE)), "  (AccountInfoDouble(ACCOUNT_EQUITY)) = ", (AccountInfoDouble(ACCOUNT_EQUITY)) );
 

Details on attached screenshots. 

 
i just deleted and installed the terminal again. Seems that solved the issue for now. But ofter back-tester generates random errors (like when i click the optimized result from mql5 cloud and then i get different results with my local back-tester). Maybe it is my PC's fault, I really don't know.
 
i still get appalling errors. I PAY for optimizations, then i get nice results, i test them at my computer and they are totally different (less profitable). These false results form the cloud are very annoying. I pay for nothing that is of any use...
 
This is absurd!! I attach video file...
Files:
 

i thought it was my computer so I tried it on another one..

I made a video from these tests. Notice the One of the last tests finally resebled the result from optimization, but when i tried to launch it again with exact same settings - it looked totally different and wiped out equity..

What the hell is going on?!

Reason: