Yeah about that, it's pretty easy to fix it. It's due to a INSERT INTO with inexistent values in the .sql structure. I can give you a hand, just PM me.
You could try this one: https://forum.multitheftauto.com/viewtopic.php?f=108&t=37086 It's called Venux RP, it's not finished and it's too far from being finished, but you could learn and create at the same time with it
You could give a try to install a windows on a Virtual Machine and see if it works. If it doesn't work on a VM that means it's something about your net connection.