I believe Equity is always zero in your Zorro version, that's why it is not documented. We update the online manual while we add features, and Equity was only implemented in the current Zorro that is not yet released. So use only the examples in your Zorro manual, not in the online version.

Balance is the total money in the account and (WinLong-LossLong) is the money earned by the strategy component. When testing a strategy with only 1 component, both are identical, but on a portfolio strategy they are different.

http://zorro-trader.com/manual/en/winloss.htm

Balance and Equity should both not be used in a strategy, as they reflect the situation of your account, not of your strategy. That was a mistake in some tutorials. Instead of Equity, use

var Gain = WinTotal - LossTotal + WinValTotal - LossValTotal;

That is the profit so far by all components of your strategy.