This script allows you to reserve common event arguments using script calls and then retrieve them in the common event.
Naturally, common events would be more flexible if you could pass in arguments, like functions in programs.
You should set the arguments before making a common event call using a script call
add_cevent_args(1, 2, 3, ...)
Then, in the common event, you can retrieve them using script calls as well
args = $game_temp.common_event_args
You would use script calls to assign them to variables or switches or anything else you might want to do.
As an example, here is a "show picture" common event that takes the name of a picture to show as an argument, and then I use methods in Picture Wrapper to display the image