Finally, save your part and give it a prefix for parts that you've made (you can use anything to help you identify it)
Close the parts editor and in the parts tab do another search to find your part again, you may have multiple versions so locate the final part you worked on
You can now try out your part, try connecting it to various other devices to make a circuit that uses all the pads
Be sure to also check out the schematic view (looks like the UNO has a weird icsp mistake but the DRV2605L is right!)
and the PCB view
You can still continue to edit the part, and do most anything that doesnt require editing a raw svg
Save it somewhere safe!
Now quit Fritzing and re-delete all the subfolders in your Documents/Fritzing/parts folder again
Now that you've cleared out all your partial edits, you can relaunch Fritzing. You'll get complaints that files are missing, that's OK! Just ignore them
Open that fpzp file you saved earlier, the part will now appear in your My Parts bin!
OK so after some time you realize you want to tweak something with the part. You don't have to start over!
Export the part to a fzpz file, copy it and rename the copy with .zip instead of .fzpz
Inside, you'll find all those SVGs again! You can edit the svg carefully and place it back in the zip, then rename it to .fzpz again.
You may need to remove the part from your My Parts bin and re-import it. You may also need to delete all the parts from your Documents/Fritzing/parts folder since Fritzing throws a fit if you have two parts with the same name