The 5.5 content is still in v6, we just added more and reorganized.

If you have content you've added to the v5.x libraries, over and above the installed content, just grab the preset files in 5.x and drop them into the preset folders in v6. Just be careful not to overwrite files with the same name.

You can also export the presets you want to keep and save them directly into the v6 preset folders.

Or save them somewhere safe, create new folders in v6 while inside the libraries and import the v5.x ones in to the new categories.

-darlisa