Dear ProfBenoliel,
According to your post message, I think it is better for you to work with ENX9 in order to finish your paper.
EN 20 has a new “OUTFIT” and another icons . I am writing a review about EN20 for Alfasoft/Clarivate and I find that EN20 is not an untamable “animal”. If you have another PC , you can install EN20 and , with a lot of time, try to “TAME” it.
I tested (as reviewer) EN versions since EndNote 1 to 20 (see Leanne/Trensofty answers) This new outfit is worthwhile to be tamed . You must spend a lot of time for this purpose. Several bugs of the ENX9 version were fixed.
I am testing EN20 on Linux PC MX with Wine 6.0 /Windows10 and with a PC with Windows 10 Pro both with 64 Bit and SSD (12GB RAM Linux and 8,0 GB Windows.
Good luck
TRENSOFTY