Rename new files, leave alone the ones I already renamed?

I built a folder structure, copied in images with crappy names to the folders they belong in, then used advanced renamer to rename the images with folder name and increment number. Total success. Now I need to add a bunch more images with crappy names, but I don't want to rename them again AND I would like increment number to continue from the highest number. Collision rules don't seem to cover this very well. Help?

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