Yes, that is what I had in my Medialab experiment (and have also tried other alternatives, but with no success). Attached is a sample .exp file that produces the error. I have yet to find a good way to interface Medialab with E-Prime scripts (and have had to program batch scripts for administering multiple .ebs files as a result). The problem is also present in the latest Medialab version (2008.1.22). I thought it might have to do with the command parameter not recognizing multiple word arguments (e.g., for experiment name and subject number), but the same thing happens when only a single-word argument (e.g., cexperiment.ebs) is used.
Jacob