Hello Ali,
that is pretty normal that you met. And no, the brokers do not have same data unfortunately, anyway EA studio would not have data import at all…Actually a single broker has differences in each server. It is important when you choose your broker, to stay with it, because when you change it, uoi have to change all your EAs…but there comes the Validator tool from EA studio that helps a lot in this cases.
So having your brokers data inside in number 1 and most important thing.
Yes, you can optimize the ea fx strategies, just check always with Monte Carlo to avoid over optimization.
So far we have no signals for bugs from EA studio.