Frame maker 13 scripting question

Hello,

I am using the following script to convert fm/mif files in a folder to PDF. The script fails in 2 places. I am using FM 13.

saveMultFilesTpPDF();

function saveMultFilesTpPDF() {

    var stop = false; 

    while( stop==false ) { 

        // Wait for 20.000 ms 

        //$.sleep(20000); 

        var fld = new Folder("c:/incoming"); 

        var filesInFld = fld.getFiles("*.fm"); 

        for(var f=0; f < filesInFld.length; f++) { 

            // process the individual file 

            $.writeln(filesInFld);

            saveDocToPdf (filesInFld, "High Quality Print"); 

        } 

        // Exit the  loop after 19:00 

        var time = new Date(); 

        if( time.getHours() > 19 ) stop = true; 

    }  

}

function saveDocToPdf (doc, jobOption) {    

    var params, returnParams, saveName, i; 

    // Set the PDF Job Option for the document.

        doc.PDFJobOption = jobOption; 

    // Replace the .fm extension with .pdf. 

  // Exceution fails on line below with "undefined is not an object"

    saveName = doc.Name.replace (/\.[^\.\\]+$/,".pdf"); 

    // Get the save parameters and set the file type to PDF> 

    params = GetSaveDefaultParams(); 

    returnParams = new PropVals(); 

    i = GetPropIndex (params, Constants.FS_FileType); 

    params.propVal.ival =Constants.FV_SaveFmtPdf; 

    // Call the document's Save method.   The script fails with

     // Exceution fails on line below with "is not a function"

    doc.Save(saveName, params, returnParams); 

}