QGIS - Create Garmin Custom Map plugin - Python Error

I am trying to create a KMZ file using the Garmin Custom Map plugin and at times it fails to execute (and I haven’t been able to establish a pattern). I get an Python Error, and the map will not be created.

I will be the first to admit, I don’t fully understand how CRS works, and would love for someone to point me to a good tutorial or info on understanding CRS.

• I create the map I want to convert to a KMZ and then use the plugin
• I get the message (Warning – Project CRS differs from WGS84 (EPSG:4326))
• Sometimes it executes and produces the map, and other times I get the below message
• WARNING Python error : An error has occurred while executing Python code: See message log (Python Error) for more details.
• When the above happens the process of producing tiles stalls