Installation problem


I've just downloaded latest version of elgg (4.3.5), uploaded the files on my server and ran installation but it fails instantly on :

Fatal error: Uncaught Error: Class 'Phpfastcache\Config\ConfigurationOption' not found in /[myserverpath]/www/[mydomain]/memory/vendor/phpfastcache/phpfastcache/lib/Phpfastcache/Drivers/Files/Config.php:21

My installation looks like that :
[Server Root]
⎜- [data-directory] (created before installation)
⎜- [www]
       ⎜- [mydomain] (my domain main folder)
               ⎜- [memory] (the main folder for my elgg instance)

I modified the .htaccess file in [memory] with :

RewriteBase /memory/

but, this doesn't help much more.

As you understand, I call the installation script from

Any idea why I get stuck at the very beginning of the installation process ?

TIA for your help !