I'm having a similar issue. Two days ago, I created a couple of Admob ad units but no ads are showing after compiling an app in Cocoon.io hours ago. I checked the unit ID numbers and there's no error after the "ca-app-pub-" I'm using the "Is Canvas+" condition to trigger the banner ads then the events of load a banner ad, set banner layout, show the banner ad occur.
After no success, I checked the config XML file:
<?xml version="1.0" encoding="UTF-8"?>
<widget xmlns="http://www.w3.org/ns/widgets" xmlns:gap="http://phonegap.com/ns/1.0" id="com.author.game" version="1.6" xmlns:cocoon="http://cocoon.io/ns/1.0" android-versionCode="10" xmlns:cdv="http://cordova.apache.org/ns/1.0">
<author href="http://website.com" email="firstname.lastname@example.org">Author Name</author>
<preference name="permissions" value="none"/>
<preference name="android-targetSdkVersion" value="23"/>
<preference name="orientation" value="landscape"/>
<preference name="fullscreen" value="true"/>
<gap:config-file platform="ios" parent="UIStatusBarHidden">
<gap:config-file platform="ios" parent="UIViewControllerBasedStatusBarAppearance">
<preference name="deployment-target" value="8.0"/>
<preference name="android-minSdkVersion" value="14"/>
<preference name="enabled" value="false"/>
<preference name="Orientation" value="landscape"/>
<preference name="Fullscreen" value="true"/>
<preference name="android-installLocation" value="auto"/>
and everything seems to compile properly.
I also used Andy's template collection and put my own numbers into the Admob plugin to test and and still no ads show even though the template app confirms the function to call banner and interstitial ads worked.
Lastly, I took one of my older apps that did have Admob implemented properly with ads showing and compiled it with both the 2.0.0 compiler and the latest compiler. Everything worked great app-wise but no ads were showing. I'm not sure if it's the Canvas+ compiler or Cocoon IO or if there's something wrong with my Admob account. I'm far from a payment threshold and from what I can see, I'm in decent standing since I've been using Admob for just under a year now.
I'm also aware that Admob has updated their policies regarding the use of ad units implemented using early Android SDKs (much lower than 14 from what I remember). But I don't think that affects anything. I'm considering moving back to XDK but really don't like how bloated Crosswalk gets when combined with HTML5. Any help would be awesome!