Can't specify the folder for the output of the batch file invoked by Excel VBA

Hi,

I am trying to run a simple batch file that runs NASTRAN in a specified folder using Excel VBA. I directly use Shell command and it works fine, however the output files go directly to "My Documents" folder instead of the folder of the batch file itself.
In other words, I cannot select the folder using the vba code.
At previous versions I was using ShellExecute but it does not work with 64-bit as far as I see. Is there something that I can use instead of the one below:

sFile = "D:\Specified_Folder\batchfilefornastran.bat"
sDefaultDir = "D:\Specified_Folder"
li = ShellExecute(hWnd, "open", sFile, vbNullString, sDefaultDir, 1)