It works with VirtualDub2 ! x64
You're the boss man !
Thank you so much magiblot !
I just had to copy the x64 version of the Nnedi3 plugin in the "plugins64+" folder of AviSynth, and it ran like a war machine !
You gave me hope !
I was effraid that I could never use this script. It's for another video with a resolution of 640x480
Original
https://media.joomeo.com/original/5adbc8270a2f0.png
Upscaled to 2160p
https://media.joomeo.com/original/5adbc8742f01c.png
Thanks to poisondeathray too !