Turn on the Automatic Shutter Design Picker
Enable the Automatic Shutter Design Picker so each shutter gets the closest-size shutter design based on its dimensions.
Setting a design's Preferences > Others > Other Preferences > Automatic Shutter Design Picker to True first asks for confirmation.
The picker decides the shutter design a shutter gets from its dimensions.
With the picker on, applying a shutter design to a shutter puts the closest-size design on it instead, with the message 'Shutter design with closest size automatically picked!'.
With the picker on, the shutter keeps its own size.