Thanks DdlV,
I agree there should be an INITRUN in that logic, so I've added that.

I am still getting a crash when trying to read in the array (note: I'm assuming it was correctly written to the file).

I think the issue could still be the length, which I've arbitrarily set to 1000. I don't think Zorro would know the length when reading in, so I'm not sure how that would work.

plotGraph sounds neat and I might explore that (I haven't used it before) but first I need to figure out the reason for the crash.
Code:
function run()
{
	StartDate = 20140101;
	EndDate = 20140212;
	BarPeriod = 15;
	int mode = 0; //1=write; 0=read
	string path = "Strategy\\dt-file-series.ini";
	vars EquityCurve;
	
	if (mode) //write mode
	{
		EquityCurve = series(EquityLong+EquityShort);
		
		if (NumOpenTotal < 5)
		{
			if(random()>0) reverseLong(1);
			else reverseShort(1);
		}
	
		if(is(EXITRUN)) file_write(path, EquityCurve, LookBack*sizeof(var));
	}
	else if(is(INITRUN)) //read mode
	{
		EquityCurve=series(0);
		file_read(path, EquityCurve, 1000);
	}
	
	plot("EquityCurve",EquityCurve[0],1,BLUE);
}