Also, what about the following statement in the manual:
In [Trade] mode, asset() causes the asset prices to be downloaded from the broker. If this is not desired or if the broker does not support that asset, add a '#' to the Symbol field in the asset list, or add an external price source such as QUANDL:, GOOGLE:, or AV:.
Would that download D1 data from the broker, if the time frame is set to 1 day bars?
