IMPORTANT: the library feature is in development so it will be better to keep a .blend file with all the real profiles geometry. The profile library can be quickly generated from this, so you won't lose them.
LIBRARY RULES:
You can name the root folder like you want
for the 'style' folder you can use only letters and numbers (example1 ecc)
To remove a 'style' folder just remove it from root folder
To delete a single profile just delete it from the 'style' folder IMPORTANT : (PNG+TXT)
The numeration is managed by the addon, for example if you remove the item _0, the next time you will save a profile in this style it will take the number 0.