Up Plus 2 CPU Upgrade with WiFi

I just purchased the CPU upgrade kit with wifi for my old Up Plus 2. I have activated it in Up Studio version . I was able to connect to wifi. Had to do a manual bed level, auto level sensor not detected. Extrude to load filament, temp stuck at 16% but nozzle temp runs away to extreme high temp, had to shut down. How do I get the cpu to recognize the hotend temps? Do I need to upgrade the hotend too? Are there any installation instructions for the new cpu kit?