The bug was writing A1 instead of A1[0]. So your script trades random and can't produce a result. Using series is explained in Workshop 4. Also you're testing an asset with some history data missing.

I do not understand your second problem, though. MT4 backtests are not unreliable because MT4 would not perform trades. They are unreliable for other reasons related to the tick-based execution, to the MQL4 structure and to in-sample testing.