I am using a TAZ 5 Lulzbot. I was trying to update the firmware via usb plug in and cura crashed every time I tried. I may have uploaded the incorrect firmware at some point. While still plugged in, the LCD screen was frozen. After trying to upload the correct firmware, I turned the printer off and on again and now the LCD screen is turning on but displays a blank blue screen. I am not sure what exactly is causing both problems. Is there a hard reset that can be performed that might be able to get it working? Any ideas? 
Grab the latest Cura LulzBot Edition from https://LulzBot.com/Cura. Follow the instructions listed to clear your cache prior to installing. Once installed, add a TAZ 5 and attempt to flash the firmware. If Cura LE closes during this process reach out to the support team at https://LulzBot.com/Support.