Fix: can not load the local KML file if the application name contains space characters.
MODIFY
plugin.xml
plugin.xml
<?xml version='1.0' encoding='utf-8'?>
-<plugin id="cordova-plugin-googlemaps" version="2.3.0-beta-20180415-2338" xmlns="http://apache.org/cordova/ns/plugins/1.0" xmlns:android="http://schemas.android.com/apk/res/android">
+<plugin id="cordova-plugin-googlemaps" version="2.3.0-beta-20180416-1033" xmlns="http://apache.org/cordova/ns/plugins/1.0" xmlns:android="http://schemas.android.com/apk/res/android">
<name>cordova-plugin-googlemaps</name>
<js-module name="BaseClass" src="www/BaseClass.js">
<runs />

MODIFY
src/ios/GoogleMaps/PluginKmlOverlay.m
src/ios/GoogleMaps/PluginKmlOverlay.m
- (NSMutableDictionary *)loadKml:(NSString *)urlStr {
+ urlStr = [urlStr stringByReplacingOccurrencesOfString:@" " withString:@"%20"];
NSError *error;
TBXML *tbxml = [TBXML alloc];// initWithXMLFile:urlStr error:&error];
if ([urlStr hasPrefix:@"http://"] || [urlStr hasPrefix:@"https://"]) {

Fix: can not load the local KML file if the application name contains space characters.