[plt-scheme] Problem with Mysterx on v370 but not v360

I  get the following error message when using v370, the program works
properly for v360.  I have applied the software patch to 370.

> (load "c:/mrs/mrs-dev.scm")
> (define MDD (open-mdd "00021022.mdd"))
> (define Scrpt (com-get-property MDD "Script"))
. COM method `Script' failed, code = 80020008: Bad variable type.

The variable has a return type of Text.

Can anyone provide some insight on what the problem may be.

Thanks
Brent.