How to specify the target document in folders through MS5.0

Hi I began to use the MaterialsScript quite recently and met a problem. I want to specify the target document which is in a folder. I looked at the example "9741022842_CEDCalculation2.zip". On the line 163, it wrote--------my \$doc = \$Documents{"\$nptEquilibrationFolder/"."\$frame.xsd"};
I tried to run that script and it also stopped at this line. The program cannot locate this file.

Does MS5.0 make any change on "specifying target document in a folder"? If yes, how can I specify it now? Thank you in advance!