Applescript in Automator behaves differently when executed from inside Automator, or as an Automator application

Hello everyone,

I'm trying to execute an Automator workflow at startup, which I do by saving the workflow as an application, and adding it to the startup list, this works fine.

My workflow works fine when executed from within Automator (ie clicking on the "Execute" button), but does not anymore when the Automator application is executed (ie. simply double clicking on my Automator file)

I have narrowed it down to an Applescript inside my workflow which fails only when the application is executed from the finder (the step works fine from within Automator). The script automatically creates an ad hoc wifi network.

The line which specifically fails is :

set menu_extras to value of attribute "AXDescription" of menu bar items

Anyone has any idea why executing the workflow from within automator, and executing it from the finder yield different results ?

The crazy thing is that all this worked fine up until a few days ago, there might have been an update since (running Mavericks 10.9.2), but nothing game-changing.