Why won't this entire KML file load into Google Maps?
 

I have a roughly 220 mile route that will show up fine in Google Earth (about 48 KB), but when I try to import it into Google Maps online, only about the first 150 or so miles of the route shows up...

I created the route in BikeToaster, and have tried both GPX and KML files in Google Earth and they work fine, but even exporting them out of Google Earth, Google Maps still won't take the whole thing...

Any ideas?

I'm going to move this to the gadget area, they might have a better idea.

Google Maps does not support multipart polygons whereas Google Earth does. If that doesn't fix it, post your KML file and I'll have a look.