Simulation not launching in Navigation Rosject

This post refers to the: Navigate with a Real Robot project for Navigation in 5 Days course.

Perhaps I am missing something simple, but in trying to start the simulation, I receive a number of errors and ultimately the Gazebo Windows opens blank! The topics that are required for the project are also not there!
command: roslaunch realrobotlab main.launch (per the project instructions…)

expected result:

I answered my own question via this post. While the errors still come up in the terminal. It does start the simulation and we just need to zoom out. The errors in the terminal do not seem to affect other functionality.