Ok, I may missunderstand something, and please correct me, but you are not supposed to replace the “com.coronalabs” with your own admob publisher Id.
The publisherId in the build settings refers to the publisher of the plugin, not to your own ad publisher Id.
Does this solve your problem?
That said, I have the following problem with the admob:
I add the plugin declaration to the build.settings just fine, and all appears fine without any errors in the corona simulator, and the app works fine, but when I try to build it for ios, in order to test it on the xcode ios simulator, the app crashes, just right after the initial loading screen.
The console records the crash, but I cannot understand what is going on.
( https://docs.google.com/document/d/1XRqyvcPcd1N3TfV-Vt43k_SQJSzZU6Fsa0h33R3Y9rA/edit?usp=sharing )
I tried running the sample code ( https://github.com/coronalabs/plugins-sample-ads-admob ) but I got exactly the same crash, at the same moment (when it tries to open the app in the xcode).
Anyone has any idea what I am doing wrong and I cannot run the sample (or my own) code?