Confused with the instruction unable to get imu raw data

[YueqiYu]

I bought the STM32 version of this robot kit.

1. The image from git here is Ubuntu 16.04 with Kinetic, the instruction says to work with Melodic which is for 18.04. Do I need to just reinstall ubuntu 18.04 and install Melodic?
2. The instruction says change MBSLIDAR to rplidar instead of delta_lidar. However, I tested both rplidar.launch and delta_lidar.launch, delta lidar worked while rplidar failed.
3. The STM32 is preprogrammed, was the program to communicate with ROS melodic or Kinetic? Or both?
4. When doing roslaunch mbsrobot bringup.launch, I got the error message like (Unable to sync with device; possible link problem or link software version mismatch such as hydro rosserial_python with groovy Arduino)

Any suggestions would be greatly appreciated!