2. In Finder, do the menu command Go > Go To Folder and copy/paste the following path:
3. Move the "Develop Presets" subfolder to your Desktop.
4. If LR now starts, edit a photo in Develop.
5. In the Presets panel, click "+" and then Import Presets. Select just one .lrtemplate file from the "Develop Presets" folder you moved to your Desktop.
6. If that preset converted and imported, then repeat step 5, selecting multiple presets at a time. There may be a "poison" preset LR can't convert, so you may have to select smaller numbers of .lrtemplate files until you find the poison preset(s).
[Use the blue reply button under the first post to ensure replies sort properly.]