Limitation of file size in xml google maps plug-in?

Hello,

I prefer to ask the question because my search are unsuccessfull.

I have installed xml google maps plug-in on my blog, it works fine, but when I want to view a kmz/kml file which is about 2 Mo and more, I have a grey area and no map. But, it works with file under 2 Mo (approximatively).
i.e : https://www.db-prods.net/blog/?p=362 (I have put two file with different file to show that xml google maps works).

So, I can deduce there is size limitation. Is it true? Or is it a problem of configuration?

Thanks in advance for your help ;).