For special applications that need to consider dynamically changed picture contents during a presentation, you can have your picture files checked.
This how you can activate this function:
First of all, add the picture to a show and design a sequence of pictures.
In the Media Pool, right-click the picture and select Properties.
Place a checkmark in checkbox Always check for newer file version and click OK.
For the function to work properly, the file name of the picture must not change. This means that the file is overwritten when there are any changes and file format and picture size in pixels remain the same.