I as of yet have not had any problem with the pics loading or the 5 day forecast dialog closing. Although, I did add a line of coding to close the 5 day forecast dialog when I pressed the close button on the main dialog.
On *:Dialog:CurrentConditions:Sclick:26: {
if !$dialog(5-DayForecast) { dialog -x CurrentConditions CurrentConditions | halt }
if $dialog(5-DayForecast) { dialog -x 5-DayForecast 5-DayForecast }
}