You can access city and time zone manager from tools menu. Time Zone manager allows you to add new cities and change time zone, DST information for existing cities.
Please note that, for every city you add to the list, you will have to specify city name, UTC offset, Longitude and Latitude. Optionally, you can specify the Daylight saving details if DST (Daylight Saving Time) applies to the city. If you enable DST for the city then you need to specify the DST start and DST end time.
To Add a new city, type in the details (city name, longitude, latitude, UTC offset) for the city and press Add new City button. If you want to modify time zone settings for any of the existing cities then select the city from list. Once you select the city, time zone data for the city will appear in the edit panel. You can then modify the settings and click Save Selected City Details button.
NOTE: You must make sure the city information you add or modify is accurate as the program will not check for the accuracy of parameters e.g. longitude or latitude cannot be cross checked by the program.