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as for fog make a new event and double click the box under list of event commands and on page 2 you will find an option called change map settings, here you have the 3 options
1 panorama
2 fog
3 battleback
put a check in the one you want then click the blue arrow at the end of the box
in fogs you have different graphics fog, clouds etc
choose fog, (there are other options but mess around with them to see what you like) click OK
now at the event editors first screen find the words event trigger and choose parallel process and there you go you have some fog.