Old printer but new in HW list

Hi all

I've a Sharebot NG printer, is now working (more or less) with Octoprint. I've some doubt:

the sd file list doesn't appear on web menu, but appear in terminal view (file in 8.3) the command sent from terminal: M20 M23 M24 are working, what I can check?

sometime I get some usb error (serial on USB) I'm trying to connect directly (serial) my printer to raspberry, any recomandation?

Thank you.

Ps I'm an printer new user!