Hello,
To answer your question, all commands and syntax allowed in the MathScript Window are allowed in the MathScript node. MathScript support for the LabVIEW application builder is a new feature of LabVIEW 8.20. If you are building an application, there are certain functions that are not supported or whose behavior changes. For more information about these commands, search the LabVIEW help for "MathScript Functions Not Supported in the LabVIEW Run-Time Engine."
I am unable to duplicate the behavior you mention in LabVIEW 8.0 or 8.20. Can you try creating an error out indicator from the MathScript node to see if any errors are being reported? If there are no errors, could you post a simple VI that illustrates the behavior you are seeing?
Thanks,
Grant M.
Staff Software Engineer | LabVIEW Math & Signal Processing | National Instruments