If EUR/JPY is not in your .fac I guess Zorro can't do anything else but to skip trades with this asset when using OptimalF as a factor to create margins. If the asset/algo is not found its OptimalF will be regarded as 0 I think. Next question is why EUR/JPY is missing, don't you have the historical prices (EURJPY_X.bar files in your history folder)?
Here is my .fac, interesting to see slightly differences in the OptimalFs, apparently we use different historical prices: