Hi,
Thanks for contacting us here about this extension.
You can create your own language following these steps, here is an example for French language.
1. Create a folder that correspond to your language in administrator/components/com_droppics/language
Ex. for a French language file your folder name will be: administrator/components/com_droppics/language/fr-FR
2. Create and name your language file properly
Ex. for a French language file: fr-FR.com_droppics.ini
3. Put that language file in administrator/components/com_droppics/language/fr-FR
4. Make sure your site language is both backend and frontend setup by default to the language you want.
If you still have issues please drop us a ticket (menu Support > Ticket), we can help with that in a private section.
Cheers,