Livecode / MariaDB UTF8 charset

[jbv at souslelogo.com]

Hi list,

I am struggling to configure the charset of a mySQL/MariaDB table
on my Livecode Hosting account.
I have a huge number of utf8 files containing names in various
alphabets (european, cyrillic, japanese, chinese, arabic...) and
I need to insert each name as a separate entry in the table.
When I run a LC script on my Mac to build a large number of
"INSERT INTO..." requests (1 for each name) and then copy/paste
these requests in phpMyAdmin, with the table charset as the default
one : utf8mb3_unicode_ci, it works : each name shows in its own 
alphabet.
But if I run the same script on the server, every character beyond
ascii 256 shows up as "?"...
I have tried other charsets, but to no avail.

My script is rather simple : a main loop that opens successively each
file (open file tfile for UTF8 read), builds the request and then runs
the sql request.

What am I doing wrong ?
Thank you in advance.

jbv