When you open the settings for a signal there is an option to limit the total number of lots that the signal can trade at any one time. However, XAUUSD, for example, reports different lot sizes for a trade of the same size as a trade in, say, EURUSD. One lot of EURUSD (100,000), with respect to margin, is roughly equivalent to 100 of XAUUSD. On my demo-account, most trades are in the order of 0.0x, except for XAUUSD, which is always x.00. Specifying a maximum number of total lots for a signal that trades both XAUUSD and EURUSD makes no sense, as setting it to 0.5 lots, for instance, would disallow all XAUUSD trades, while still allowing most of the EURUSD-trades. If it were possible to specify a maximum amount that is allocated to any single signal, this would not happen. Also, the number of lots shown in the statistics for the account don't make sense for the same reason. It's adding up apples and oranges and coming up with a number that isn't useful.