When attempting to insert a color coding legend into the model drawing pane, the following error occurs:
"Attempted to read or write protected memory. This is often an indication that other memory is corrupt".
In at least one case, this was due to a problem with video hardware drive on the Windows operating system. Try updating the video card drivers associated with the graphics hardware on your computer. If you have more than one video hardware/display adapter showing (such as onboard CPU video like "Intel HD" plus a discrete video card like NVidia), try changing the settings so one is the default that is used for the program. See more here:
Updating video drivers and troubleshooting video hardware issues
Error opening or creating project: Attempted to read or write protected memory