Hi Alex and all our thoughts go out to you in Ukraine with the nasty situation you are living with now.
I can help with the cable plug ins so get in contact with me and I can guide you through it (or most of it). I worked at SSL from 1980-87, have installed many studios since then and am the wiring moderator on this site. Are you on Whatsapp so we can have a free call?
Get in contact via email first (jimlassenwiring@btinternet.com) and we can take it from there. I am a wiring person , not a tech so, I can't fix anything but know a lot about the wiring.
Regards from Jim Lassen.