With 8 EAs all set at 1% (which is recommended in the settings file) your total risk is 1% if all 8 EAs hit SL. This would cause you to fail the max daily loss of 5% and you would lose your account. It is rare for all 8 EAs hit SL on the same day but it could happen. So, in my opinion I would want to prevent this from occurring. If it were me I would set the lot size to 1/2 the size shown in the set file. This would limit the maximum daily loss to 4% so the account would not fail the daily maximum loss requirement of 5%.
The set file lot sizes are the lot sizes Petko used to pass the FTMO challenge. The lot size in the set file will help to pass the FTMO challenge in a minimum of time. However, the set file lot sizes are quite risky. To pass the challenge in the shortest period of time requires taking added risk. So if you use the lot sizes as shown in the set files then if you blow the account you have to start a new challenge until you pass.
An alternate approach is to reduce risk and take longer to pass the challenge.
It is up to each trader to set the lot size of any robot to the risk level the trader is willing to accept.
Alan,