Lines across screen during use following screen change

Hey Rob! That's quite the odd behavior! Usually that's a sign of the LCD connection being faulty, even if it's seated properly. I'd check the pins in the connections, both device side and display side. The thing to check for is dust/debris in the connection or bent pins. If everything looks pristine, and the device still behaves strangely, then I'd say it's an LCD issue deeper in the display, and you should seek replacement. Best of luck with your repair!