I would like to be able to have different versions of a file with different crop sizes.
I would also like to crop the photo and come back later and decide to do something entirely different, crop-wise. However, I cannot find the orginial version of my file inside Lightroom.
My workaround has previously been to export the file as a TIF back into Lightroom, however, I made the mistake of cropping too soon before I realized I wanted to go various directions with this photo.
Now I'm trying to re-import the file from its source and Lightroom won't let me import a duplicate because one time in the past I said as a preference, "don't import duplicates." How do I change this preference?
If I understand correctly, you could create Virtual Copies of photos that you'd like to have with different crops (or any other develop settings, for that matter).
As for the "don't import duplicates" option, you can uncheck it from the import window (in the top left 'File Handling' panel). When synchronizing a folder, you can check the "show import dialog before importing", otherwise you won't be able to change the duplicates option.