AE Trader and Financial are shipped with limited number of historical data files (EURUSD, Gold, S&P 500)

in MT4\history\GCIFinancial-Demo program folder that is set as path to external MT4 files.

The availability of other financial instruments depends on those available in Metatrader 4 installed on your computer.

The instruments list displays all currency pairs, stocks, commodities and indexes GCI Trading provides, but you may any MT4 broker on your choice.
The instruments for those historical files are available on your computer are printed in black text.
Those are available from broker but not added in Metatrader are grayed out.

For more information click Metatrader 4 installation and configuration and How to get and set MT4 data path buttons on Prefs->Metatrader 4 tab.