Question

Is there a way to obtain the current setting for desktop wallpaper change either using Apple Script or defaults read? Basically I want to know by looking at the plist file if the option of changing wallpaper every X minutes is enabled or not.

Answer 1

See the AppleScript dictionary for the Desktop Suite class of the System Events helper app. It contains the property:

picture rotation (integer) : never, using interval, using login, after sleep

There are separate values for each desktop, for instance, if you have more than one monitor active. For example:

tell application "System Events"
    get picture rotation of its first desktop
end tell