we had similar issues with NameMapping/Aliases when they we're using them. We let TC generate it automatically when recording scripts. But it wasn't very useful, generating many strange errors, including "Exceptions" and "Process not found". But this problems were somewhat random. We figured it out that it was the way our windows were being mapped. Unfortunately, we decided to stop using NameMapping and made our trainees re-generate all our Test Cases.
If there is any way on using NameMapping, we certainly would, but thus far it would do more harm to us than good i think.