I'm trying to run paper trading in an Interactive Brokers (IB) trial account using Zorro, but was unable to figure out how to get the symbols for future contracts. I mainly need CL (crude oil), GC (gold), and SI (silver) front month contracts.

I did try following the example of ES (for some reason it's commented out) in AssetsIB.csv, which is in the format of ES-FUT-20180921-ES-GLOBEX. However, for some (SI) I get the error message that the product is unavailable, and for some others I get the error message that the currency is missing.

So I'm wondering if there is a rule to construct IB symbols for future contracts in Zorro? Thanks!