Not sure if I'm asking the right question. Never used Google Earth Pro before, but I have a 2GB KMZ file and I can't open it. Is there a way to break it down further or is there a limit to how large a kmz can be for Google Earth Pro?
I don't think KMZ has a size limit, but I'm pretty sure that a 2gb kmz file would be hard to manage by Google Earth/Pro. I would suggest you to clip it into different regions, so that you have smaller files.
You can open/change format/clip the KML using different softwares, the ones that I would use are Global Mapper / ArcGIS with Xtools.
But perhaps someone knows about a specific (and cheaper) tool for doing this.