For language strings not translated in Farsi, you can join the Persian translation team on Transifex:
After creating your free account, ask to join the Persian team. I will add you when i will have the notification.
You could then start first to translate missing strings in com_icagenda site used for frontend.
About the date displayed using Persian date format, it is using Joomla site language... so i wonder if i can add there an option to switch date formatting off...
Latest version : 3.7.14
We recommend every user to keep your iCagenda updated. Don't forget to have your Joomla!™ up-to-date!