Yes. On Windows Starry Night looks to the Windows registry to determine the time format. If it can't find a registry entry for regional date settings then it defaults to the 12 hour clock. Unfortunately UK Windows does not automatically place the date format in the registry where Starry Night expects to see it. To work around this, you should open the "Regional Settings" control panel, switch the time format to something other than the current setting, click OK, then reopen the "Regional Settings" control panel and switch to the 24-hour clock. After restarting Starry Night it should be using the new time format. On the Macintosh you can reset the time format from the Date and Time control panel. After restarting Starry Night it should be using the new time format.