ISSUE with OS 10.11 El Capitan and EXTFS

I used Paragon EXTFS for Imac with 10.6.8 and it worked perfectly.
I changed my mac and I'm using 10.11 El Capitan.
I imported the new version of Paragon EXTFS.
I need to format USB Key to EXT3.
Then :
the first time the format of the key failed.
I retried after formating the key with EXFAT again.
It takes a long time to format the key in EXT3 (more than 60 minutes for 64 Go) during writing inode tables (details given in the window of Paragon - Cf the attachments below).

Is someone got the same isssue?
Do I really need to disable the System Integrity Protection as I read somewhere on the web?
Or using the terminal as Paragon advices?
Thanks for your answers...


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Imac El Capitan - 10.11.6 - 27 inch, late 2013 - 3,2 GHz Intel Core i5, RAM 16 Go 1600 MHz DDR3 -

Do you need an expert opinion or prefer to be advised by someone else?

Thank you John,

Finally I succed to format the USB Key. It takes a long time by the way. Probably it's normal.
:D
best regards
L