ExtendScript - Waiting Message?

I'm having a bit of an issue when trying to select my target in the ExtendScript ToolKit. When I select InDesign as the target, it launches the application but ESTK sits there with a message box saying "Waiting; press ESC to abort..." It appears that it's not able to communicate with the process at all, and I'd love a little help debugging this. Anyone have any ideas?

Thanks!