
Please note that I'm still on the "introduction"...
I've check on phpinfo:
max_execution_time 120
max_file_uploads 20
max_input_nesting_level 64
max_input_time 120
max_input_vars 1000
post_max_size 128M
memory_limit 768M
upload_max_filesize 128M
session.gc_maxlifetime 1440
opcache.force_restart_timeout 180
memcached.sess_connect_timeout 1000
Dunno what is wrong...

PS:
I've tested with php 5.6, 7.0 and 7.1
And I've mysqli on the config.php file.
Kudos