Hello,
I have exact the same problem with soundbooth. And also that extended script is working fine with photoshop. I have tested it on 4 different computers. Updated windows to sp3, and updated all adobe software.
So it's definitely not a mess in the system (beside the mess of software 1,2 Gb you have to install for only soundbooth!!, Cool edit pro, which adobe took over from which soundbooth is a spin off, was only 20Mb....)
The technical help form adobe won't look at this if you don't buy the software first. But after some pressure they looked at the problem but couldn't find anything about it in there system.
Please advise how to solve this
Richard